Netbox is not yet compatible with Python 3.9

Author: cimnine

.github/workflows/push.yml

@@ -15,7 +15,7 @@ jobs:
         - '' # use the default of the DOCKERFILE
         - python:3.7-alpine
         - python:3.8-alpine
-        - python:3.9-rc-alpine
+        # - python:3.9-rc-alpine # Netbox does not work with Python 3.9 yet.
       fail-fast: false
     runs-on: ubuntu-latest
     name: Builds new Netbox Docker Images