try out alternate py installer

Author: abeaucha

.github/workflows/build_unittest.yml

@@ -84,7 +84,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python
-      uses: actions/setup-python@v2
+      uses: adam-beauchamp/setup-python@v2
       with:
         python-version: '3.7'
     - name: Get latest CMake and ninja