What's Changed
* use `register_pre_save_hook` by timkpaine in https://github.com/timkpaine/jupyterlab_autoversion/pull/90
* Update to JLab 4, fix several issues with git sha ordering in git python, add support for diffing by timkpaine in https://github.com/timkpaine/jupyterlab_autoversion/pull/129
**Full Changelog**: https://github.com/timkpaine/jupyterlab_autoversion/compare/v0.3.6...v0.4.0