Update which requirement from 7.0 to 8.0

[musicinmybrain]

This Pull Request fixes/closes #{issue_num}.v N/A

It changes the following:

• Updates the which dependency in Cargo.toml from 7.0 to 8.0
• Updates Cargo.lock with cargo update which.

I followed the checklist:

• [ ] I added unittests N/A, nothing new to test
• [x] I ran make check without errors. (On Fedora 42, I needed to use CC=clang CXX=clang++ because onig_sys does not build with GCC 15 due to incompatible pointer types in the oniguruma C code. I also needed python-unversioned-command installed, and I needed to cargo install cargo sort. None of this has anything to do with this PR.)
• [x] I tested the overall application
• [ ] I added an appropriate item to the changelog N/A, I think. It looks like you do not include dependency updates in the changelog.

[cruessler]

Are there any reasons to update this dependency specifically? Just curious, I’m not questioning that these kinds of updates are generally useful.

[musicinmybrain]

Are there any reasons to update this dependency specifically? Just curious, I’m not questioning that these kinds of updates are generally useful.

Based on https://github.com/harryfei/which-rs/blob/8.0.0/CHANGELOG.md, the immediate benefits are rather minor: better handling of I/O errors, and one fewer dependency.

(I filed this PR while updating the rust-which package in Fedora. I patched packages as needed to avoid a rust-which7 compat package, and it’s our policy to offer patches upstream.)

[extrawurst]

one fewer dependency.

Thats actually the opposite if you check the diff on the lock file. I would defer this one until we have a chance to not duplicate the rustix dependency