AuroraCloneRefresh: Intermittent lambda timeouts

[zhelyan]

• the delete cluster lambda, aurora_delete_clone.py times out as it blocks and waits for the cluster to be deleted. The wait loop should be decoupled as a state machine step using the existing lambda that checks the cluster status - aurora_check_status.py

• the lambda that creates the cluster may also timeout as it blocks and waits for the cluster to be cloned and then for a primary instance to be available