Enforce importlib-metadata<5 for tests otherwise Entrypoint object attribute errors

Author: awig

setup.py

@@ -58,6 +58,7 @@
         'requests<=2.25.1',  # https://github.com/psf/requests/pull/5810
         'xarray',
         'tables',
+        'importlib-metadata<5'
         'pvlib==0.8.0',
         'scipy<1.9',
         'statsmodels',