Merge pull request #24 from not522/fix-allennlp

Fix the CI with AllenNLP

.github/workflows/tests.yml

@@ -62,6 +62,11 @@ jobs:
         pip install --progress-bar off .[test]
         pip install --progress-bar off .[all]
 
+        # TODO(not522): Remove the version constraint when splitting this workflow.
+        # This constraint is necessary to use the old Pydantic.
+        # See https://github.com/pydantic/pydantic/issues/5821.
+        pip install "typing_extensions<4.6.0"
+
         # Install optuna from specified repository, otherwise from optuna/optuna.
         $( test ${{ inputs.repository_name }} && test ${{ inputs.branch_name }} ) \
           && pip install git+https://github.com/${{ inputs.repository_name }}@${{ inputs.branch_name }} \