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>

crates/eframe/Cargo.toml

@@ -61,7 +61,7 @@ default_fonts = ["egui/default_fonts"]
 glow = ["dep:egui_glow", "dep:glow", "dep:glutin-winit", "dep:glutin"]
 
 ## Enable saving app state to disk.
-persistence = ["dep:home", "egui-winit/serde", "egui/persistence", "ron", "serde"]
+persistence = ["egui-winit/serde", "egui/persistence", "ron", "serde"]
 
 ## Enables wayland support and fixes clipboard issue.
 ##
@@ -165,7 +165,6 @@ glutin-winit = { workspace = true, optional = true, default-features = false, fe
   "egl",
   "wgl",
 ] }
-home = { workspace = true, optional = true }
 
 # mac:
 [target.'cfg(any(target_os = "macos"))'.dependencies]