Bump container registry to v3.12.0

What does this MR do?

3.12.0 (2021-10-11)

Bug Fixes

• handlers: only log that a manifest/blob was downloaded if the method is GET (19d9f60)

Features

• datastore: add created_at timestamp to online GC review queue tables (3a38a0a)
• datastore: calculate total manifest size on creation (4c38d53)
• handlers: log metadata when a new blob is uploaded (83cb07e)

Related issues

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion

Required

• Merge Request Title, and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Integration tests added to GitLab QA
• The impact any change in container size has should be evaluated