fix workflow

Author: emptymalei

.github/workflows/tests.yaml

@@ -34,6 +34,7 @@ jobs:
           python -m pip install --upgrade pip
           pip install pytest
           if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+          pip install .
       - name: pre-commit
         uses: pre-commit/[email protected]
       - name: Test with pytest