fix: add pytest to CI install step

Author: safishamsi

.github/workflows/ci.yml

@@ -24,7 +24,8 @@ jobs:
       - name: Install dependencies
         run: |
           pip install -e ".[mcp,pdf,watch]"
+          pip install pytest
 
       - name: Run tests
         run: |
-          pytest tests/ -q --tb=short
+          python -m pytest tests/ -q --tb=short