Improve Review Apps scheduled cleanup

What does this MR do?

This improves a bit the Review Apps scheduled cleanup by moving it to the build stage (so that it's not affected by failing tests) and adding action: stop to it to better reflect the intent.

This also removes the depth clone limitation since it could prevent the job from actually start, e.g.: https://gitlab.com/gitlab-org/gitlab-ee/-/jobs/202861939

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Performance 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

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team