Update extensionKind

[cvaldev]

Fixes #4379

The old "ui" value (as a string) maps to this type for backwards compatibility, but is considered deprecated.

[J-Fields]

I think ["ui", "workspace"] is correct, but not 100% sure. Do you have a good explanation for this, or did you choose this only because it's equivalent to what we had before?

[cvaldev]

@J-Fields Sorry, I should have cited my quote. I chose it because according to this it is the equivalent of what we had before.

"extensionKind": ["ui", "workspace"] — Indicates the extension prefers to run as a UI extension, but does not have any hard requirements on local assets, devices, or capabilities. When using VS Code, the extension will run in VS Code's local extension host if it exists locally, otherwise will run in VS Code's workspace extension host if it exists there. When using VS Online's browser-based editor, it will run in the remote extension host always (as no local extension host is available). The old "ui" value (as a string) maps to this type for backwards compatibility, but is considered deprecated.

[J-Fields]

Cool, just checking. I think this is right, and if it causes issues for anyone we can always change it. Thanks!