Ensure project backfilling has finished

What does this MR do and why?

This migration acts as a gate-keeper for other migrations related to project namespace back-filling so that other migrations, like !81121 (merged), !79204 (merged) and other that depend on project namespace back-filling cannot be run unless project namespace back-filling has finalised successfully.

Requirements

• this migration timestamp 20220322071127 should be after !77371 (merged) which is 20220301093434
• this migration should be part of a release after !77371 (merged) was deployed(%14.9) as it will raise exception during migration if !77371 (merged) did not finish. So we need to let !77371 (merged) finish first, that is what this migration tries to ensure. So we want this merged in %14.10

re !82176 (merged)

Screenshots or screen recordings

These are strongly recommended to assist reviewers and reduce the time to merge your change.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• [-] I have evaluated the MR acceptance checklist for this MR.