Add workflow stubtests for macos (#5384)

* Add macos to stubtest

* Add general darwin stubtest exception file

* Adding exceptions and platform ifs

.github/workflows/tests.yml

@@ -103,7 +103,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: ["ubuntu-latest", "windows-latest"]
+        os: ["ubuntu-latest", "windows-latest", "macos-latest"]
         python-version: [3.6, 3.7, 3.8, 3.9, '3.10.0-beta.1']
       fail-fast: false