Python 3.9 got released and broke the tests

.gitlab-ci.yml

@@ -2,13 +2,13 @@ stages:
   - test
   - quality-assurance
 
-py38:
+py39:
   stage: test
   image: python:3-alpine
   before_script:
     - apk add --no-cache libmagic
     - pip install tox --no-cache-dir
-  script: tox -e py38
+  script: tox -e py39
 
 linters:
   stage: quality-assurance