Rewrite the `ci.py` script in Rust
It would seem that I would learn by now that any script written in Python will become unmaintainable sooner or later, but alas..
r? `@marcoieni`
try-job: aarch64-gnu
try-job: dist-x86_64-linux-alt
try-job: x86_64-msvc-ext2
Fixes: https://github.com/rust-lang/rust/issues/137013