Fix a bunch of other low-hanging style lints (#36498)

- **Fix a bunch of low hanging style lints like unnecessary-return**
- **Fix single worktree violation**
- **And the rest**

Release Notes:

- N/A

crates/markdown_preview/src/markdown_renderer.rs

@@ -111,11 +111,10 @@ impl RenderContext {
     /// buffer font size changes. The callees of this function should be reimplemented to use real
     /// relative sizing once that is implemented in GPUI
     pub fn scaled_rems(&self, rems: f32) -> Rems {
-        return self
-            .buffer_text_style
+        self.buffer_text_style
             .font_size
             .to_rems(self.window_rem_size)
-            .mul(rems);
+            .mul(rems)
     }
 
     /// This ensures that children inside of block quotes