Replace all sort with unstable sort (#38427)

["When applicable, unstable sorting is preferred because it is generally
faster than stable sorting and it doesn’t allocate auxiliary
memory."](https://doc.rust-lang.org/std/vec/struct.Vec.html#method.sort)

Binary also reduced by 1KB in Release.

Testing: No behaviour change as semantically all current usage does not
have any pair with `std::cmp::Ordering::Equal`.

Signed-off-by: Euclid Ye <euclid.ye@huawei.com>

components/constellation/constellation.rs

@@ -5401,7 +5401,7 @@ where
         };
         // In order to get repeatability, we sort the pipeline ids.
         let mut pipeline_ids: Vec<&PipelineId> = self.pipelines.keys().collect();
-        pipeline_ids.sort();
+        pipeline_ids.sort_unstable();
         if let Some((ref mut rng, probability)) = self.random_pipeline_closure {
             if let Some(pipeline_id) = pipeline_ids.choose(rng) {
                 if let Some(pipeline) = self.pipelines.get(pipeline_id) {