chore: Fix violations of elided_named_lifetimes (#18330)

I compile Zed from nightly build pretty often and I've noticed that
we're getting a few hits on new rustc lint:
https://github.com/rust-lang/rust/pull/129207

Release Notes:

- N/A

crates/editor/src/editor.rs

@@ -11515,7 +11515,7 @@ impl Editor {
         &'a self,
         position: Anchor,
         buffer: &'a MultiBufferSnapshot,
-    ) -> impl 'a + Iterator<Item = &Range<Anchor>> {
+    ) -> impl 'a + Iterator<Item = &'a Range<Anchor>> {
         let read_highlights = self
             .background_highlights
             .get(&TypeId::of::<DocumentHighlightRead>())