controlPlaneEndpoint set up through load balancer should be possible … (#3888)

* controlPlaneEndpoint set up through load balancer should be possible  even in single master setups

Enable load balancer for single-master setups
Fixes an issue where single-master setups are not reachable using the usual admin.conf from outside the cluster. 

controlPlaneEndpoint set up through load balancer should be possible  even in single master setups

* add fix to other api versions

* remove obsolete check completely

* remove check, pass 2

* removes checks in client configuration

* delete 'and'