fix the temporary scheduler was mistakenly started the hb service

src/storage/tx/ob_xa_ctx.cpp

@@ -2115,6 +2115,8 @@ int ObXACtx::try_heartbeat()
   const int64_t now = ObTimeUtility::current_time();
   if (original_sche_addr_ != GCTX.self_addr()) {
     // temproray scheduler, do nothing
+  } else if (OB_ISNULL(xa_branch_info_) && xa_trans_state_ > ObXATransState::IDLE) {
+    // do nothing
   } else if (OB_ISNULL(xa_branch_info_)) {
     ret = OB_ERR_UNEXPECTED;
     TRANS_LOG(ERROR, "unexpected branch count", K(ret), K(*this));