Merge pull request #533 from ndw/fix-python

Attempt to fix CI build issue

Author: ndw

.github/workflows/build-branch.yml

@@ -64,7 +64,7 @@ jobs:
 
       - name: Install platform-independent Python modules
         run: |
-          python3 -m pip install pygments==2.14.0 click cython
+          python3 -m pip install pygments==2.14.0 click cython python-dateutil
 
       # Test the build on Mac