ci: pin ubuntu runner to 24.04 in workflows

[xtqqczze]

Closes #12005

Pin the Ubuntu GitHub Actions runner version to avoid unintentionally introducing a dependency on the kernel and glibc version shipped with Ubuntu 26.04 when ubuntu-latest is updated. This ensures that future runner upgrades remain explicit and deliberate decisions.

[oech3]

No. user should update their Ubuntu to 26.04 or use musl binary. This is not what we should care about.

[oech3]

Also you are trying to remove the most important test cases.

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/date/date-locale-hour (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/pr/bounded-memory (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/tail-n0f (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/cut/bounded-memory (passes in this run but fails in the 'main' branch)

[oech3]

At least, this should be restricted to MSRV CI.

[xtqqczze]

I've pinned all Ubuntu jobs for now, though I agree we should be more specific.

[oech3]

Please stop. This does not help.

[oech3]

One of a possibility is CI breakage caused by uutils/coreutils installed on Ubuntu 26.04, but it should be fixed by just apt-geting GNU.

[oech3]

Please close this PR. I really don't want to use time for reverting your PR or bumping version.

Also you should try to use musl binary on Ubuntu 22.04 .
You don't need to install it.

[oech3]

(Legacy Rust + latest Linux) and (Newest Rust + legacy Linux) does not making a sense. I suggest to just pin MinRustV CI only.
Pinning everything is not acceptible as it rejects catching regression for stty on the most common targets anyway.