[Feature Request] Support Jupyterlab 4

[wenmin-wu]

Jupyterlab 4 has some great improvements that convinced me to move from Jupyter Notebook to Jupyterlab. But this extension is not compatible with Jupyterlab 4. I'm thinking with Completer and InlineCompleter provided by Jupyterlab 4. We can code in JupyterLab as efficient as coding in vscode using this great extension tabnine-vscode. Since lots of Data Scientists use jupyterlab for their work, making this extension available for Jupyterlab 4 can also increase the number of tabnine users.

[wenmin-wu]

I quickly setup one for personal usage: code, which could be useful for those who share the interest.