Add Jupyter extensions

[filiptronicek]

This PR adds missing Microsoft Jupyter extensions.

[filiptronicek]

ms-toolsai.jupyter-renderers is sooo flustrating to publish: I can package it up using the provided commands, but it's so hard to do: I only achieved success while using Node 14 (Node 16 requires more config). If we ever want to just publish a version of the extension pre-packaged, we can do so with ms-notebook-renderers.vsix.zip [GitHub doesn't allow .vsix file uploads].

[filiptronicek]

Linking microsoft/vscode-notebook-renderers#96 here because it might help with figuring out how to package it properly.