Refactor general resource cleanup scripts
The resource deletion scripts used in the general resource cleanup scheduled pipeline need to be refactored. There are similar functions that could be consolidated to a base class. There also needs to be improved logging, the delete_before date needs to be moved to an environment variable, and dry_run capabilities need to be extended to each of the 4 scripts. There was a recent request to remove certain resources on production and the scripts had to be run locally only because there wasn't a delete_before variable since the resources were very recent.
Part of https://gitlab.com/gitlab-com/gitlab-OKRs/-/work_items/6490