[Bug]: Add a CI job to verify the zot configuration files

[andaaron]

zot version

v2.0.0

Describe the bug

The make verify-config make target used to be run by the CI workflow, as part of make, but that changed in #1832.
At the moment the examples are no longer verified.

We should make sure we run the make verify-config for every PR.

As part of this task, we should also fix the existing issues with the configuration files (some of them do not use the separate file for LDAP bind credentials)

To reproduce

Run make verify-config and see errors in the existing configuration files.

Expected behavior

No response

Screenshots

No response

Additional context

No response