[2.x] Support @jupyter/ydoc 2.x

[fcollonval]

Fixes #309

@jupyter/ydoc 2.x is identical to 1.x - the major bump was a consequence of a change in the Python package.

[github-actions[bot]]

:point_left: Launch a Binder on branch _fcollonval/jupyter_serverydoc/309-211-shows-jupyterlab-compatibility-warning-with-jupyterlab-42

[fcollonval]

On Binder build, the result of jupyter labextension list is

+ jupyter labextension list
JupyterLab v4.2.1
/srv/conda/envs/notebook/share/jupyter/labextensions
        jupyter-offlinenotebook v0.2.2 enabled  X
        jupyterlab_pygments v0.3.0 enabled OK (python, jupyterlab_pygments)
        @jupyter-widgets/jupyterlab-manager v5.0.10 enabled OK (python, jupyterlab_widgets)
        @jupyter-server/resource-usage v1.0.2 enabled OK (python, jupyter-resource-usage)
        @jupyter/collaboration-extension v2.1.1 enabled OK (python, jupyter_collaboration)

   The following extensions may be outdated or specify dependencies that are incompatible with the current version of jupyterlab:
        jupyter-offlinenotebook

   If you are a user, check if an update is available for these packages.
   If you are a developer, re-run with `--verbose` flag for more details.

Disabled extensions:
    @jupyterlab/filebrowser-extension:defaultFileBrowser

[davidbrochart]

Failures seem to be caused by the latest release of AnyIO. In this PR, AnyIO now emits a ResourceWarning on unclosed memory object streams. So we should either explicitly close memory object streams (best) or ignore this warning in tests.

[davidbrochart]

This is happening in pycrdt-websocket. Another (temporary) option would be to pin anyio <4.4.0.

[fcollonval]

Failures seem to be caused by the latest release of AnyIO. In this PR, AnyIO now emits a ResourceWarning on unclosed memory object streams. So we should either explicitly close memory object streams (best) or ignore this warning in tests.

Thanks for highlighting the source of the error. I add the new warning to the ignore list of pytest in 4a311c7.

[davidbrochart]

Thanks. I guess we should update the screenshots in the UI tests, as we did in 3.x?

[davidbrochart]

@fcollonval there are conflicts, sorry for not merging earlier. Do you want to rebase?

[brichet]

@fcollonval I can rebase it if you want, I also need this compatibility.

[fcollonval]

@fcollonval I can rebase it if you want, I also need this compatibility.

Thanks @brichet please feel free to do so. My oss bandwidth is tight currently.

[brichet]

Failing tests seem not related to this PR.