test python 3.7 and 3.8

Author: markusressel

.github/workflows/pythonpackage.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       max-parallel: 4
       matrix:
-        python-version: [ 3.9, "3.10" ]
+        python-version: [ 3.7, 3.8, 3.9, "3.10" ]
 
     steps:
       - uses: actions/checkout@v1