Remove use of the home crate

[ehuss]

The home crate is no longer intended for general use, but instead only for use by cargo and rustup. It is recommended to switch to std::env::home_dir instead.

Note that there are a few things to consider here:

• home_dir's behavior was changed on Windows to use USERPROFILE (similar to how home worked) in 1.85 via Fix and undeprecate home_dir() rust-lang/rust#132515.
• home_dir's deprecation was removed in 1.87 via Undeprecate env::home_dir rust-lang/rust#137327.
• home_dir uses a fallback on an empty HOME as of 1.90 via If HOME is empty, use the fallback instead rust-lang/rust#141840.

[Byron]

Thanks a lot for bringing this up!

The home crate seems to be used only from gix-path, and there it's a fallback only. So I think it should be OK to use std::env::home even today, assuming that the application is built with a compiler as recent as 1.85.