Bump version to 0.16.2-gitlab.54

Release 0.16.2-gitlab.54.

Changelog

• !190 (merged) — update-labels command and a LabelUpdater driver interface, implemented by the google driver. gitlab-runner uses it to refresh the runner_manager_heartbeat label on tracked machines (gitlab-runner!7264, released separately). Older plugins return the same error as drivers without label support.
• !187 (merged) — stop, start, and inspect recover the zone of machines whose create never resolved one, instead of failing with an empty-zone 400. Lookup failures propagate from GetState instead of reading as state.None.
• !191 (merged) — the Google COS readiness gate is split into two independent opt-ins. --google-cos-docker-network-readiness-gate now only waits for cloud-init. A new --google-cos-docker-network-readiness-url runs the container egress probe against the given URL, and only when set. The previous probe fetched the metadata server on :80 from a container, which the worker firewall drops by design, so it could never pass on a correctly-firewalled worker.

Related issues

• gitlab-com/gl-infra/production-engineering#29652 (closed) — this release puts the label-write half of the heartbeat into the S3 bucket the runner-manager image builds from.
• https://gitlab.com/gitlab-com/gl-infra/production-engineering/-/work_items/29697 — the K8s GPU shard is drained pending this release; the readiness-URL change is what lets it come back with the gate enabled.
• gitlab-com/gl-infra/ci-runners#29 (closed) — runner manager centralization, which these changes support.

Release steps

After merge, tag the merge commit as v0.16.2-gitlab.54. The tag pipeline uploads binaries to the stable S3 bucket and creates the release entry.