clippy: fix several lint warns (#32126)

As seems #31500 still remain opened here's the next partial fix.

Fixed list: `unused_mut`, `clippy::needless_borrow`,
`clippy::match_ref_pats`, `clippy::borrow_deref_ref`, `clippy::ptr_eq`,
`clippy::unnecessary_cast`, `clippy::derivable_impls`,
`clippy::collapsible_match`, `clippy::extra_unused_lifetimes`,
`clippy::map_clone`, `clippy::manual_filter`.


- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes are part of #31500.
- [x] These changes do not require tests because are only cosmetic.

components/script/dom/navigator.rs

@@ -120,8 +120,8 @@ impl Navigator {
     fn shrink_gamepads_list(&self) {
         let mut gamepad_list = self.gamepads.borrow_mut();
         for i in (0..gamepad_list.len()).rev() {
-            if gamepad_list.get(i as usize).is_none() {
-                gamepad_list.remove(i as usize);
+            if gamepad_list.get(i).is_none() {
+                gamepad_list.remove(i);
             } else {
                 break;
             }