It's time to update Docker Engine

This post addresses a specific CI/CD failure mode caused by the incompatibility between Alpine Linux 3.14 and older Docker Engine versions. It details the problem encountered at GitLab with the `ruby:2.7` image, the temporary workaround of pinning to Alpine 3.13, and the permanent solution of updating Docker Engine on GitLab.com instance-level Runners and the `docker:dind` service to at least version 20.10.6. It also outlines the requirements for users to update their own environments.