[CI] debian + RHEL updates (backport #985)

[mergify]

This is an automatic backport of pull request #985 done by Mergify.
Cherry-pick of 0bcb77b has failed:

On branch mergify/bp/iron/pr-985
Your branch is up to date with 'origin/iron'.

You are currently cherry-picking commit 0bcb77b.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   .github/workflows/humble-debian-build.yml
	new file:   .github/workflows/iron-debian-build.yml
	modified:   .github/workflows/iron-rhel-binary-build.yml
	new file:   .github/workflows/rolling-debian-build.yml
	modified:   .github/workflows/rolling-rhel-binary-build.yml

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   .github/workflows/humble-rhel-binary-build.yml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[christophfroehlich]

@bmagyar you dropped the humble workflow files with #820 now causing this conflict. I think it can be merged as it is, let's add them to avoid future merge conflicts?

[bmagyar]

I see, let's do that