Add changelog for version 3.0

[yuvipanda]

I choose to make it 3.0 because not needing websockify is a big enough change that will break some dependent projects that relied on using it to detect if the X server was up or not (like https://github.com/sunu/jupyter-remote-qgis-proxy/blob/baf0d373c2f965a60bc6fe038bb04cacc8df8cf5/jupyter_remote_qgis_proxy/utils.py#L44)

[github-actions[bot]]

:point_left: Launch a binder notebook on this branch for commit dfa81234ca65af83b082462409ece8cc0ea52205

I will automatically update this comment whenever this PR is modified

[manics]

Other than those comments go ahead with a release!