* Upgrade example for JupyterLab 4

Switch to extension template (#229)
Add notifications example (#230)
Add an example package for the use of metadata-form (#208)
Add codemirror extension example (#231)

Co-authored-by: Frédéric Collonval <fcollonval@gmail.com>
Co-authored-by: Florence Haudin <haudin.florence@gmail.com>
Co-authored-by: Nicolas Brichet <nicolas.brichet@quantstack.net>

* Bump to final package version

* Upgrade documents example

* Update documents README

* Update template

* Make ICollaborativeDrive optional

* Fix tests

* Install browser for integration tests

* Fix tests

* Improve robustness for metadata form ui test
Break documents test at browser_check

* Fix documents packaging

* Remove _version.py file

* Yet another attempt to fix integration tests

* Improve test robustness and some fixes

* Update codemirror snapshot

* Finally nail the culprit in metadata form test

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Co-authored-by: Michał Krassowski <5832902+krassowski@users.noreply.github.com>
Co-authored-by: Florence Haudin <haudin.florence@gmail.com>
Co-authored-by: Nicolas Brichet <nicolas.brichet@quantstack.net>