gitlab/gitlab-runner:alpine docker image is stale

When I tried updating my instance of gitlab-runner:alpine image this morning from 14.10.1 to 15.0.0 -- and tried to pull gitlab/gitlab-runner:alpine image, I got no new image. It seems that gitlab/gitlab-runner:alpine was never updated.

As a workaround I'm using now gitlab/gitlab-runner:alpine-v15.0.0, but this requires extra work.