fix tests.yml

Author: KtrauM

.github/workflows/tests.yml

@@ -24,8 +24,7 @@ jobs:
       with:
         python-version: 3.9
     - name: Install dependencies
-        run: |
-          pip install -r requirements.txt
+        run: pip install -r requirements.txt
     - name: Run tests
       run: >-
         python -m