Update doc/raketasks/cleanup.md

What does this MR do?

This MR adds a warning above the rake task sudo gitlab-rake gitlab:cleanup:repos which is "currently" (since 11 months) not working as expected (cf. https://gitlab.com/gitlab-org/gitlab-ee/issues/24633) and seems to mark all existing repositories as orphaned.

Currently while following the docs, it pictures that using this task will only rename abandoned repositories - but thats not what it is doing currently.

Related issues

gitlab-org/gitlab-ee#24633

Author's checklist

• Follow the Documentation Guidelines and Style Guide.
• If applicable, update the permissions table.
• Link docs to and from the higher-level index page, plus other related docs where helpful.
• Apply the ~Documentation label.

Review checklist

All reviewers can help ensure accuracy, clarity, completeness, and adherence to the Documentation Guidelines and Style Guide.

1. Primary Reviewer

• Review by a code reviewer or other selected colleague to confirm accuracy, clarity, and completeness. This can be skipped for minor fixes without substantive content changes.

2. Technical Writer

• Optional: Technical writer review. If not requested for this MR, must be scheduled post-merge. To request for this MR, assign the writer listed for the applicable DevOps stage.

3. Maintainer

1. Review by assigned maintainer, who can always request/require the above reviews. Maintainer's review can occur before or after a technical writer review.
2. Ensure a release milestone is set and that you merge the equivalent EE MR before the CE MR if both exist.
3. If there has not been a technical writer review, create an issue for one using the Doc Review template.

closed

mentioned in merge request gitlab-foss!32973 (closed)

reopened

Reopened due to hint by @rpaik -> gitlab-foss!32973 (comment 217312248)

added 3301 commits

• d1cb75ba...58f0af10 - 3300 commits from branch gitlab-org:master
• 187be982 - Merge branch 'master' into docs/schwedenmut-master-patch-66935

Compare with previous version

added 1 commit

• 11615807 - Removed wrong spaces

Compare with previous version

added devopscreate groupsource code labels

added Community contribution label

@nick.thomas can you help with the review?

Thanks for this @schwedenmut , I'm happy to merge this as-is while we schedule a proper fix!

approved this merge request

merged

mentioned in commit 969f73b8

changed milestone to %12.3

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added workflowstaging label

This merge request has been deployed to the GitLab.com environment gprd-cny in GitLab auto-deploy version 12.3.201909182329-c544ca4f88b.da0c0542d51.

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added workflowcanary label and removed workflowstaging label

This merge request has been deployed to the GitLab.com environment gprd in GitLab auto-deploy version 12.3.201909200727-8bdd831ba23.7ea35a0e137.

A list of all the deployed commits can be found here.

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added workflowproduction label and removed workflowcanary label