RFR: 8372733: GHA: Bump to Ubuntu 24.04

[Erik Joelsson]

On Fri, 28 Nov 2025 11:56:26 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> GHA have changed `ubuntu-latest` to `ubuntu-24.04` some time this year. Ubuntu also mentions `22.04` would come off standard support in April 2027, following the usual 5-year cycle. So it is a good time to switch to `24.04` for our current runners.
> 
> We did the switch to `22.04` 2.5 years back, so we are following the similar 2-year-ish cadence here. 
> 
> Additional testing:
>  - [x] GHA

Marked as reviewed by erikj (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/28555#pullrequestreview-3525446158