message: fix use incorrect lock
diff: @@ -17,11 +17,11 @@ void CreateEdgeProcessor::process(const cpp2::CreateEdgeReq& req) {
  {
  // if there is an tag of the same name
  // TODO: there exists race condition, we should address it in the future
  - folly::SharedMutex::ReadHolder rHolder(LockUtils::edgeLock());
  + folly::SharedMutex::ReadHolder rHolder(LockUtils::tagLock());
  auto conflictRet = getTagId(spaceId, edgeName);
  if (nebula::ok(conflictRet)) {
  LOG(ERROR) << "Failed to create edge `" << edgeName
  - << "': some edge with the same name already exists.";
  + << "': some tag with the same name already exists.";
  resp_.set_id(to(nebula::value(conflictRet), EntryType::EDGE));
  handleErrorCode(nebula::cpp2::ErrorCode::E_CONFLICT);
  onFinished();
  