降级macos ci环境

Change-Id: Ib94915974f50c4afd5318c895d9c11eaaf9b9ba1

Author: tonychanchen

.github/workflows/tencent_official.yml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   Build:
-    runs-on: macOS-latest
+    runs-on: macos-10.15
     steps:
     - uses: actions/checkout@v2
     - name: pod cache