Enforce pandas version before testing due to bug in testing module

Author: druzm

.github/workflows/python-package.yml

@@ -39,4 +39,5 @@ jobs:
         flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
     - name: Test with pytest
       run: |
+        pip install pandas==2.0.2
         pytest -m "not plotter" -s