editor: Shrink size of Inlay slightly (#39089)

And some other smaller cleanup things I noticed while reading through
some stuff

Release Notes:

- N/A *or* Added/Fixed/Improved ...

crates/editor/src/inlay_hint_cache.rs

@@ -3571,7 +3571,7 @@ pub mod tests {
         editor
             .visible_inlay_hints(cx)
             .into_iter()
-            .map(|hint| hint.text.to_string())
+            .map(|hint| hint.text().to_string())
             .collect()
     }
 }