Update to Jupyter Releaser v2

[jtpio]

We should update the repo so it's compatible with the Jupyter Releaser v2:

• Add the releaser workflows to the repo
• Set up bot account: Set up jupyterlab-contrib-bot for releases jupyterlab-contrib.github.io#42
• Clean up the check release workflow to remove the pip install . step:

  jupyterlab-link-share/.github/workflows/check-release.yml

  Line 51 in d0a3f63

  pip install .