feat(elasticache): add UserGroup and ServerlessCache constructs

Author: maramure

packages/aws-cdk-lib/aws-elasticache/lib/common.ts

@@ -0,0 +1,14 @@
+/**
+ * Engine type for ElastiCache users and user groups
+ */
+export enum UserEngine {
+  /**
+   * Valkey engine
+   */
+  VALKEY = 'valkey',
+
+  /**
+   * Redis engine
+   */
+  REDIS = 'redis',
+}