Fix CI: pin ruff, work around chumpy build failure

Author: isarandi

.github/workflows/python-publish.yml

@@ -51,7 +51,8 @@ jobs:
 
       - name: Verify package
         run: |
-          pip install dist/*.whl
+          pip install dist/*.whl --no-deps
+          pip install numpy scipy chumpy --only-binary=:all: || pip install numpy scipy
           python -c "import smplfitter; print(smplfitter.__version__)"
 
       - uses: actions/upload-artifact@v4