修正警告: moving a local object in a return statement prevents copy elision

https://www.viva64.com/en/w/v828/

编译器会对返回本地变量优化([Named] Return Value Optimization (RVO/NRVO)),
无论是 C++11 之前还是之后, 添加 move 后反而会影响该优化.

C++ Core Guidelines F.48: Do not return std::move(local)

src/Record/HlsMakerImp.cpp

@@ -63,9 +63,9 @@ string HlsMakerImp::onOpenSegment(int index) {
         WarnL << "create file failed," << segment_path << " " << get_uv_errmsg();
     }
     if (_params.empty()) {
-        return std::move(segment_name);
+        return segment_name;
     }
-    return std::move(segment_name + "?" + _params);
+    return segment_name + "?" + _params;
 }
 
 void HlsMakerImp::onDelSegment(int index) {