Update Rust Toolchain to 1.80.1

[roypat]

With toolchain version >= 1.80 some crates had regressions due to stricter file descriptor ownership tracking in the standard library (e.g. tracking the same fd in multiple File objects, and thus resulting in multiple close calls for the same fd will now cause panics in the drop impl). We started getting fix-up PRs (rust-vmm/kvm#272), so update the CI to 1.80.1 to make sure we don't regress again after merging fixes.

Summary of the PR

Please summarize here why the changes in this PR are needed.

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