GCC 14.2.0 support

[DL6ER]

What does this implement/fix?

A few changes without functional changes needed to get compatible with Alpine 3.21 (GCC 14.2 and Linux 6.12).

Opening as draft right now as we can update the building container only when it has been tagged.

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Related issue or feature (if applicable): pi-hole/docker-base-images#100

Pull request in docs with documentation (if applicable): N/A

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[DL6ER]

Note: The failing 386 test is expected. file's output changed. This test will pass once we use the newer container.

[yubiuser]

Just maybe one of the functions could be renamed a bit, I think they are quite similar and easy to get mixed.

check_capability and check_capabilities

[DL6ER]

Their very similar names are intentionally the way they are. One requires an argument (checking for one), the other not (checking for all). IMO this is sufficient as extra distinction.