fix topk bug which cause ctc score diff

speechx/speechx/utils/math.cc

@@ -79,11 +79,13 @@ void TopK(const std::vector<T>& data,
     int cur = values->size() - 1;
     while (!pq.empty()) {
         const auto& item = pq.top();
-        pq.pop();
     
         (*values)[cur] = item.first;
         (*indices)[cur] = item.second;
          
+        // item if reference, must pop here
+        pq.pop();
+
         cur--;
     }
 }