feat(docker-jans): change persistence entry check to read configuration

[iromli]

Current wait_for_persistence checks for existing client with specific inum (pulled from configmap role_based_client_id).
In hybrid persistence scenario where there are shared clients used across 2 domain/namespace/cluster, the role_based_client_id configmap in certain namespace/cluster may not match the one in shared clients hence the entrypoint couldn't get the required entry.
Unfortunately this will lead to pod stuck in wait phase as it assume persistence is not pre-populated with data yet.

The wait_for_persistence should check for configuration entry instead (i.e. ou=jans-auth,ou=configuration,o=jans) and this entry should be inserted after any client creation.