feat: Convert Deepnote block types to .ipynb format#2

andyjakubowski wants to merge 2 commits intomaindeepnote/jupyterlab-deepnote:mainfrom

andy/oss-91-convert-deepnote-block-types-to-ipynb-formatdeepnote/jupyterlab-deepnote:andy/oss-91-convert-deepnote-block-types-to-ipynb-formatCopy head branch name to clipboard