Add code style check and fix commands

Author: nickspaargaren

.github/workflows/tests.yml

@@ -12,6 +12,12 @@ jobs:
         cache: 'pip'
     - name: Install dependencies
       run: pip install -r requirements.txt
+    - uses: actions/cache@v3
+      with:
+        path: ~/.cache/pip
+        key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-pip-
 
   code-style:
     name: Code style