dsccommunity/FailoverClusterDsc

AI Summary: The FailoverClusterDsc module's `Cluster` resource needs to be updated to handle idempotency correctly. Currently, attempting to apply the configuration twice results in an error because it doesn't check if the node is already part of the correct cluster before attempting to add it. The solution involves adding logic to check for existing cluster membership, and if the node is already in the target cluster, the operation should succeed without error. If the node is in a different cluster, it should either be removed from the incorrect cluster and added to the correct one, or an appropriate error should be raised.