Use Ubuntu 24.04 Noble for GitHub CI

[christophebedard]

• The ubuntu-24.04 GitHub actions runner might not be available until August 2024 (Add Ubuntu 24.04 Noble Numbat actions/runner-images#9691), so just use Docker
• We seem to now need to explicitly set the default shell to bash to get source to work (possibly due to running in Docker and not the runner itself)

[christophebedard]

Rolling is unfrozen now, so this is ready for review.

[fujitatomoya]

lgtm.

if i am not mistaken, workflow is only effective for rolling branch? this is off topic from this PR, but how we can manage the PR against jazzy iron and humble? only CI?

[christophebedard]

Yes, this is only for the rolling branch. Each branch needs to have its own workflow config.