Bump container registry to v3.18.1 (pre)

What does this MR do?

3.18.1 (2021-12-10)

Bug Fixes

• revert enable PostgreSQL pageinspect extension (2c2825c)

3.18.0 (2021-12-09)

Bug Fixes

• datastore: do not panic if database credentials are wrong (cfc51e7)

Features

• datastore: calculate deduplicated repository size (#486 (closed)) (86d68c1)
• datastore: enable PostgreSQL pageinspect extension (74f6521)
• datastore: extend support for Helm Charts media types (ff2fd80)
• gc: add dangling and event labels to online GC run metrics (738cf24)
• gc: log creation timestamp and event of GC tasks (e0133c3)

Related to gitlab-org/container-registry#532 (closed).

Author Check-list

Please read the Contributing document and once you do, complete the following:

• Assign to the correct reviewer per the contributing document
• Apply the correct metadata per the contributing document
• Link to related MRs for applying the changes on other environments
• Link to related Chef changes
• If necessary link to a Criticality 4 Change Request issue

Reviewer Check-list

• Reviewed the diff jobs to confirm changes are as expected
• No changes shown in the diffs not associated with this MR - This may require a rebase or further investigation

Applier Check-list

• Make sure there is no ongoing deployment for the affected envs before merging (see #announcements slack channel)