Update description for RBAC flag in Key Vault (#15161)

* Update description for RBAC flag in Key Vault

* Update keyvault.json

* Update keyvault.json

* Update keyvault.json

Author: jlichwa

specification/keyvault/resource-manager/Microsoft.KeyVault/preview/2020-04-01-preview/keyvault.json

@@ -1260,7 +1260,7 @@
         "enableRbacAuthorization": {
           "type": "boolean",
           "default": false,
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
         },
         "createMode": {
           "type": "string",
@@ -1345,7 +1345,7 @@
         },
         "enableRbacAuthorization": {
           "type": "boolean",
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
         },
         "softDeleteRetentionInDays": {
           "type": "integer",

specification/keyvault/resource-manager/Microsoft.KeyVault/preview/2021-04-01-preview/keyvault.json

@@ -1258,7 +1258,7 @@
         "enableRbacAuthorization": {
           "type": "boolean",
           "default": false,
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
         },
         "createMode": {
           "type": "string",
@@ -1347,7 +1347,7 @@
         },
         "enableRbacAuthorization": {
           "type": "boolean",
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
         },
         "softDeleteRetentionInDays": {
           "type": "integer",

specification/keyvault/resource-manager/Microsoft.KeyVault/stable/2019-09-01/keyvault.json

@@ -1292,7 +1292,7 @@
         "enableRbacAuthorization": {
           "type": "boolean",
           "default": false,
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the vault is created with the default value of false. Note that management actions are always authorized with RBAC."
         },
         "createMode": {
           "type": "string",
@@ -1381,7 +1381,7 @@
         },
         "enableRbacAuthorization": {
           "type": "boolean",
-          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored (warning: this is a preview feature). When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
+          "description": "Property that controls how data actions are authorized. When true, the key vault will use Role Based Access Control (RBAC) for authorization of data actions, and the access policies specified in vault properties will be  ignored. When false, the key vault will use the access policies specified in vault properties, and any policy stored on Azure Resource Manager will be ignored. If null or not specified, the value of this property will not change."
         },
         "softDeleteRetentionInDays": {
           "type": "integer",