ci: check code style and spelling

.gitlab-ci.yml

@@ -3,14 +3,25 @@ image: python:3.8
 stages:
   - test
 
-before_script:
+.install_requirements:
   - apt-get -qq update
   - python3.8 -m venv python
   - . python/bin/activate
   - pip3 install -r requirements.txt
-  - cp config/sample-production.engine.ini config/engine.ini
 
 run_test_cases:
   stage: test
+  before_script:
+    - *install_requirements
+    - cp config/sample-production.engine.ini config/engine.ini
   script:
     - ./run.sh test
+
+check_style:
+  stage: test
+  before_script:
+    - apt-get --quiet update
+    - apt-get --quiet --yes install codespell make python3-flake8
+  script:
+    - make lint
+    - make spelling