Fix clippy::len_zero lint style violations (#36589)

Related: #36577

Release Notes:

- N/A

---------

Signed-off-by: Umesh Yadav <git@umesh.dev>

crates/buffer_diff/src/buffer_diff.rs

@@ -2129,7 +2129,7 @@ mod tests {
             diff.hunks_intersecting_range(Anchor::MIN..Anchor::MAX, &working_copy, cx)
                 .collect::<Vec<_>>()
         });
-        if hunks.len() == 0 {
+        if hunks.is_empty() {
             return;
         }