Prepare 10.8 RC3 release

Main release issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/45897

Summary

This MR prepares 10-8-stable for %10.8 (RC3) by merging 10-8-stable-prepare-rc3 into 10-8-stable.

MR Filter for ~"Pick into 10.8" MRs

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests?label_name%5B%5D=Pick+into+10.8&scope=all&state=merged

Note to leave in MRs

Picked into https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18772, will merge into `10-8-stable` ready for `10.8 RC3`

/unlabel ~"Pick into 10.8"

Steps

1. Cherry-pick https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18771

• This can be done by checking out 10-8-stable-prepare-rc3 locally and using git cherry-pick -m1 MERGE_COMMIT_SHA
• Note: The quickest way to check the MERGE_COMMIT_SHA is to go the Discussion tab in the Merge Request. The merge commit SHA will be visible right before the comment of it being merged. Sometimes the merge commit SHA will not be available in the Discussion tab, in those cases you have to look for it in the commits tab for master

1. Push changes every so often and verify that the MR has been included
2. If there are any conflicts while picking MRs then attempt to resolve them; otherwise, create a new MR against the 10-8-stable-prepare-rc3 branch and assign it to the author of the conflicting files.
3. Merge CE-to-EE using one of the workflows described in the Merge CE stable changes to EE docs

• Note: Often, after a release has been tagged, the VERSION file in ee will have a conflict. Accept the -ee one

1. Once this MR is green merge it to stable, preferably with a manual fast-forward merge to minimize waiting time, as described in Merging preparation MRs into stable

Checklist

• https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18771 has been picked

• Conflicts resolved

• No new commits have introduced directly to the stable branch while this MR was in progress. If there are, ensure these are merged into EE and check for a green pipeline after merging this MR.