Remove unneeded 'static lifetimes on &strs in constants (#8698)

This PR removes unneeded `'static` lifetimes on `&str`s stored in
`const` declarations.

This addresses some Clippy lints about
[`redundant_static_lifetimes`](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_static_lifetimes).

In item-level `const` declarations we can rely on lifetime elision and
use the default `'static` lifetime.

Note that associated constants still require an explicit `'static`
lifetime, as explained in
https://github.com/rust-lang/rust/issues/115010.

Release Notes:

- N/A

crates/editor/src/editor.rs

@@ -8644,7 +8644,7 @@ impl Editor {
         let mut cwd = worktree.read(cx).abs_path().to_path_buf();
         cwd.push(".git");
 
-        const REMOTE_NAME: &'static str = "origin";
+        const REMOTE_NAME: &str = "origin";
         let repo = project
             .fs()
             .open_repo(&cwd)