chore(ci): add step to install test dependencies in GitHub Actions workflow to ensure all necessary packages are available before running tests

Author: tumf

.github/workflows/test.yml

@@ -27,6 +27,10 @@ jobs:
         python -m pip install --upgrade pip
         pip install uv
 
+    - name: Install test dependencies
+      run: |
+        uv install --category test
+
     - name: Run tests
       run: |
         uv run pytest