Roll out actionlint everywhere.

[sengi]

We use GitHub Actions for a lot of important stuff and all(?) of our config for it is YAML. GHA's YAML interface is full of gotchas and footcannons, so a decent linter is a no-brainer.

We want actionlint to be a mandatory pre-merge check on all GOV.UK repos that use GitHub Actions.

(Removed Tasklists as these are deprecated)

[jasonBirchall]

Suggestion to use this tool:
https://github.com/alphagov/bulk-changer

[AgaDufrat]

List of the PRs generated

[AgaDufrat]

We should also update the docs so the check is added to any new repos: https://docs.publishing.service.gov.uk/manual/github-new-repo.html

[jasonBirchall]

@dj-maisy, what's the latest on this?

[AgaDufrat]

There's also https://github.com/alphagov/bulk-merger which can be helpful.

[dj-maisy]

This is now done, barring one final PR:

• https://github.com/alphagov/govuk_chat_private/pull/13