Update to ServiceStack.Redis Info

Added minimum version detail for ServiceStack.Redis client per https://docs.servicestack.net/releases/v5.6#servicestacktext as suggested by customer as a follow-up comment.

Author: Mike-Ubezzi

articles/azure-cache-for-redis/cache-remove-tls-10-11.md

@@ -48,7 +48,7 @@ Most applications use Redis client libraries to handle communication with their
 Redis .NET clients use the earliest TLS version by default on .NET Framework 4.5.2 or earlier, and use the latest TLS version on .NET Framework 4.6 or later. If you're using an older version of .NET Framework, you can enable TLS 1.2 manually:
 
 * **StackExchange.Redis:** Set `ssl=true` and `sslprotocols=tls12` in the connection string.
-* **ServiceStack.Redis:** Follow the [ServiceStack.Redis instructions](https://github.com/ServiceStack/ServiceStack.Redis#servicestackredis-ssl-support).
+* **ServiceStack.Redis:** Follow the [ServiceStack.Redis](https://github.com/ServiceStack/ServiceStack.Redis#servicestackredis-ssl-support) instructions and requires ServiceStack.Redis v5.6 at a minimum.
 
 ### .NET Core