Investigate GitLab GPG expiry extension failures

GET should be handling the situation when the GPG for the GitLab repository is rotated or extended by always installing the GPG key first.

However this appears to no longer work as while the task completes apt continues to fail, which shows as Failed to update apt cache: unknown reason in Ansible output but the real error is:

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://packages.gitlab.com/gitlab/nightly-builds/ubuntu focal InRelease: The following signatures were invalid: EXPKEYSIG 3F01618A51312F3F GitLab B.V. (package repository signing key) <packages@gitlab.com>
W: Failed to fetch https://packages.gitlab.com/gitlab/nightly-builds/ubuntu/dists/focal/InRelease  The following signatures were invalid: EXPKEYSIG 3F01618A51312F3F GitLab B.V. (package repository signing key) <packages@gitlab.com>
W: Some index files failed to download. They have been ignored, or old ones used instead.

Task is to investigate.