add transit encryption mode support for redis instance resource

mmv1/products/redis/api.yaml

@@ -190,3 +190,13 @@ objects:
           - :STANDARD_HA
         default_value: :BASIC
         input: true
+      - !ruby/object:Api::Type::Enum
+        name: transitEncryptionMode
+        description: |
+          The TLS mode of the Redis instance, If not provided, TLS is disabled for the instance.
+
+          - SERVER_AUTHENTICATION: Client to Server traffic encryption enabled with server authentcation
+        values:
+          - :SERVER_AUTHENTICATION
+          - :DISABLED
+        default_value: :DISABLED

mmv1/third_party/terraform/tests/resource_redis_instance_test.go

@@ -143,6 +143,7 @@ resource "google_redis_instance" "test" {
     maxmemory-policy       = "noeviction"
     notify-keyspace-events = ""
   }
+  transit_encryption_mode = "SERVER_AUTHENTICATION"
 }
 `, name)
 }