Don't fail on warnings for ipywidgets downstream tests

Author: martinRenou

.github/workflows/downstream.yml

@@ -38,6 +38,7 @@ jobs:
         uses: jupyterlab/maintainer-tools/.github/actions/downstream-test@v1
         with:
           package_name: ipywidgets
+          test_command: pytest -vv -raXxs --durations 10 --color=yes
 
   jupyter_client:
     runs-on: ubuntu-latest