CI: use default version of gcc on Ubuntu VM

[claudioandre-br]

asan is failing a lot (and seems random).

Well, it is probably not a good idea to use gcc-13 + ASAN on Ubuntu-latest (the default gcc is 11).

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It looks better now, using the PR, but we can't be sure without more random testing.

[claudioandre-br]

CI is clean. Forcing another run for testing.

[solardiz]

asan is failing a lot (and seems random).

My guess was that we simply exceeded some kind of GitHub Actions resources for our org, with my recent multiple quick pushes to bleeding-jumbo, which resulted in several sets of CI jobs running concurrently. I've since rerun the failed jobs on a couple of commits, and they all succeeded.

I think it made sense for us to use newer gcc's ASan, but I also don't mind your changes here. So I'll merge.

[claudioandre-br]

My guess was that we simply exceeded some kind of GitHub Actions resources for our org,

I saw this ASAN AddressSanitizer:DEADLYSIGNAL error a week ago [1] (and nothing was running). But since it's random, I can't say much about it.

The org in the situation was me.

[1] https://github.com/claudioandre-br/JohnTheRipper/actions/runs/8248714971 versus, e.g., https://github.com/openwall/john/actions/runs/8351346753/job/22859525043