Prepare Attestation SDK for GA release (#20760)

Author: LarryOsterman

sdk/attestation/Azure.Security.Attestation/CHANGELOG.md

@@ -1,6 +1,6 @@
 # Release History
 
-## 1.0.0-beta.3 (Unreleased)
+## 1.0.0 (2021-05-11)
 
 ### Changed
 

sdk/attestation/Azure.Security.Attestation/src/Azure.Security.Attestation.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Description>This is the project which implements the Microsoft Azure Attestation client API and package</Description>
     <AssemblyTitle>Azure SDK Template</AssemblyTitle>
-    <Version>1.0.0-beta.3</Version>
+    <Version>1.0.0</Version>
     <PackageTags>Azure Template</PackageTags>
     <TargetFrameworks>$(RequiredTargetFrameworks)</TargetFrameworks>
   </PropertyGroup>