Remove dependency home (#8307)

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

<!--
Please read the "Making a PR" section of
[`CONTRIBUTING.md`](https://github.com/emilk/egui/blob/main/CONTRIBUTING.md)
before opening a Pull Request!

* Keep your PR:s small and focused.
* The PR title is what ends up in the changelog, so make it descriptive!
* If applicable, add a screenshot or gif.
* If it is a non-trivial addition, consider adding a demo for it to
`egui_demo_lib`, or a new example.
* Do NOT open PR:s from your `master` branch, as that makes it hard for
maintainers to test and add commits to your PR.
* Remember to run `cargo fmt` and `cargo clippy`.
* Open the PR as a draft until you have self-reviewed it and run
`./scripts/check.sh`.
* When you have addressed a PR comment, mark it as resolved.

Please be patient! I will review your PR, but my time is limited!
-->

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.lock

@@ -1269,7 +1269,6 @@ dependencies = [
  "glow",
  "glutin",
  "glutin-winit",
- "home",
  "image",
  "js-sys",
  "log",
@@ -2204,15 +2203,6 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
 
-[[package]]
-name = "home"
-version = "0.5.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc627f471c528ff0c4a49e1d5e60450c8f6461dd6d10ba9dcd3a61d3dff7728d"
-dependencies = [
- "windows-sys 0.61.2",
-]
-
 [[package]]
 name = "http"
 version = "1.4.2"