Make the flags logging dynamic

What does this MR do?

While debugging some behaviors locally, I noticed that not all the flags/options were being logged in the startup.

This MR aims to fix that by adding a test that fails if a new flag/option is either not logged or marked as nonLoggableFlags.

keys that were missing

• "gitlab-cache-cleanup"
• "gitlab-cache-expiry"
• "gitlab-cache-refresh"
• "gitlab-client-http-timeout"
• "gitlab-client-jwt-expiry"
• "gitlab-retrieval-interval"
• "gitlab-retrieval-retries"
• "gitlab-retrieval-timeout"
• "listen-proxy"
• "max-uri-length"
• "server-shutdown-timeout"
• "server-write-timeout"
• "zip-http-client-timeout"
• "zip-open-timeout"

TODO

• Feature flag
  • Added feature flag:
  • This feature does not require a feature flag
• I added the Changelog trailer to the commits that need to be included in the changelog (e.g. Changelog: added)
• I added unit tests or they are not required
• I added acceptance tests or they are not required
• I added documentation (or it's not required)
• I followed code review guidelines
• I followed Go Style guidelines