One big cleanup pass of clippy lints

Co-authored-by: Mikayla <mikayla@zed.dev>

crates/util/src/lib.rs

@@ -128,7 +128,9 @@ struct Defer<F: FnOnce()>(Option<F>);
 
 impl<F: FnOnce()> Drop for Defer<F> {
     fn drop(&mut self) {
-        self.0.take().map(|f| f());
+        if let Some(f) = self.0.take() {
+            f()
+        }
     }
 }