[Python Client] Pin importlib_metadata==7.2.1 to fix broken PyPI CI…

… (#363)

.github/workflows/publish.yaml

@@ -43,6 +43,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           pip install -e ".[all]"
+          pip install importlib_metadata==7.2.1
 
       - name: Build PyPI
         run: |