Migrate to new notebook workspace edit api

[mjbvz]

We've working on cleaning up how extensions can apply edits to notebooks. As part of this, we will be removing the notebookEditorEdit API proposal and replacing it with a new notebookWorkspaceEdit api proposal. Main changes:

• Edits are now expressed using a NotebookEdit object
• We've removed the NotebookEditor.edit edit builder function entirely

The functionality of this new api should be the same as the old API. You can find the current api here

Here's a list of current consumers:

• Jupyter @rchiodo Use new API to delete/insert/replace cells vscode-jupyter#10117
• Jupyter powertoys @rchiodo Adopt new notebookWorkspaceEdit proposal vscode-jupyter-powertoys#33
• LiveShare @alyssajotice @fubaduba Adopt the new vscode notebookWorkspaceEdit API proposal live-share#4682
• Dot net interactive @brettfo, @colombod Adopt the new vscode notebookWorkspaceEdit API proposal dotnet/interactive#2036

[mjbvz]

Merged in new proposal with #149128

[mjbvz]

Hey @rchiodo, can you please take a look at the new API proposal and me know if you have any feedback on it? We want to make sure it looks ok for Jupyter before asking other extensions migrate over too

[rchiodo]

Just glancing at it looks fine. We'd have to port to it I think before we could comment on what might or might not work.

[mjbvz]

All users have now been migrated over. Just need to remove the api itself now