Remove feature flag for GPG cleanup

What does this MR do?

This will make sure that when cleanup fails, an exception will be raised.

This also increases the time we'll try to cleanup in Sidekiq, as it appeared we still had some failures there.

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers