Remove dependency home (#8307)

Replaces `home::home_dir` with `std::env::home_dir` as these functions
do the exact same thing

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Removes dependency home from eframe by replacing `home::home_dir` with
`std::env::home_dir`. `home` was probably originally used since
`std::env::home_dir` was once deprecated because of a bug. Post Rust
version 1.87 this has been fixed and now these two functions do exactly
the same thing.

* [X] I have followed the instructions in the PR template

Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>

Cargo.toml

@@ -96,7 +96,6 @@ glow = "0.17.0" # Can't update to 0.18: wgpu 30's wgpu-hal pins glow 0.17, so bu
 glutin = { version = "0.32.3", default-features = false }
 glutin-winit = { version = "0.5.0", default-features = false }
 harfrust = "0.12.0"
-home = "0.5.12"
 image = { version = "0.25.6", default-features = false } # Can't update to 0.25.7+: it needs png 0.18, which only matches resvg once resvg moves to tiny-skia 0.12 — blocked, see resvg below
 itertools = "0.15.0"
 jiff = { version = "0.2.35", default-features = false }