Automatic merge from submit-queue (batch tested with PRs 48012, 47443, 47702, 47178)
incluster config will be used when creating external shared informers.
**What this PR does / why we need it**:
Previously the loopback configuration was used to talk to the server.
As a consequence a custom API server was unable to talk to the root API server.
This PR changes the above by using incluster configuration to create shared informers.
**Release note**:
```release-note
NONE
```