auto-build weekly instead of manually

[darinpope]

Build once a week instead of requiring a manually launched build. This will help as we onboard more BOM maintainers since some won't have Job.BUILD access on ci.jenkins.io.

Testing done

Verified with pipeline syntax generator

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did

[gounthar]

Will it work even if the main branch is not locked?

[MarkEWaite]

This morning I remembered why we hadn't used this technique earlier. When building a release of the plugin BOM, we need to lock the master branch so that pull requests from plugin releases are not merged during the build. When a pull request is merged, it will cancel the release job that is running.

I've enabled branch protection on the master branch now that the build is running and will create and pin the issue for the release.

[timja]

This morning I remembered why we hadn't used this technique earlier. When building a release of the plugin BOM, we need to lock the master branch so that pull requests from plugin releases are not merged during the build. When a pull request is merged, it will cancel the release job that is running.

I've enabled branch protection on the master branch now that the build is running and will create and pin the issue for the release.

Easily do-able with a scheduled action that locks the branch that runs before the Jenkins job