Unitialized cluster shutdown can leak a connection
Description
If the cluster instance fails to initialize due to a timeout, the control connection might be connecting or reconnecting but `Shutdown` and `Dispose` do not dispose it so there's a potential for a connection leak.
If the cluster instance fails to initialize due to a timeout, the control connection might be connecting or reconnecting but `Shutdown` and `Dispose` do not dispose it so there's a potential for a connection leak.