JupyterEventsVersionWarning emited by jupyter-events 0.11.0

[frenzymadness]

When running tests of jupyter-server with the latest version of jupyter-events, the output is full of messages like:

FAILED tests/services/contents/test_manager.py::test_copy_big_dir[jp_contents_manager3] - jupyter_events.utils.JupyterEventsVersionWarning: The `version` property of an event schema must be a string. It has been type coerced, but in a future version of this library, it will fail to validate. Please update schema: https://events.jupyter.org/jupyter_server/contents_service/v1

And those warnings cause the tests to fail.

[krassowski]

It looks like #1481 will address this?

[frenzymadness]

It looks like #1481 will address this?

I think so, yes. I can test it when the new version is released.