* Use correct canonical URL while building docs (#6829)
As noted in https://github.com/readthedocs/readthedocs.org/pull/10224 with the current configuration the canonical URL is wrong with different sphinx builds. For instance the "latest" docs point to "stable". This leads to apps like Mastodon to generate previews to pages which don't exist since they rely on
<link rel="canonical" href="https://jupyter-notebook.readthedocs.io/en/stable/notebook_7_features.html" />
This should fix that.
* Renaming migration file to `migrating_to_notebook7`
* Use the correct name
* fix ref
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Co-authored-by: Ashwin V. Mohanan <9155111+ashwinvis@users.noreply.github.com>
Aidan Feldman
Andrii Ieroshenko
Jeremy Tuloup