Merge pull request #72 from StackStorm/add_py_3.9

Add python 3.9

Author: amanda11

.github/workflows/lint-and-unit-tests.yml

@@ -33,6 +33,7 @@ jobs:
         version:
           - "3.6"
           - "3.8"
+          - "3.9"
     steps:
       - uses: actions/checkout@v3
 
@@ -60,3 +61,4 @@ jobs:
         run: |
           make .lint
           make .unit-tests
+