Bump container registry to v3.9.0

What does this MR do?

3.9.0 (2021-08-18)

Features

• handlers: enable migration mode to be paused (9d43c34)

3.8.0 (2021-08-17)

Bug Fixes

• handlers: deny pushes for manifest lists with blob references except manifest cache images (79e854a)
• handlers: enable cross repository blob mounts without FS mirroring (98fe521)
• handlers: handle blob not found errors when serving head requests (2492b4e)
• storage: never write blob links when FS mirroring is disabled (0786b77)

Features

• datastore: allow removing a connection from the pool after being idle for a period of time (0352cc3)
• storage/driver/s3-aws: add IRSA auth support (de69331)

Performance Improvements

• handlers: lookup single blob link instead of looping over all (46f1642)

Related issues

container-registry#435 (closed)

container-registry#436 (closed)

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
• Pipeline is green on dev.gitlab.org if the change is touching anything besides documentation or internal cookbooks
• trigger-package has a green pipeline running against latest commit

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for the GitLab Chart opened