* Use --exclude to skip node_modules
Instead of copying and then deleting them. This will also catch some
node_modules directories that were missed.
* Remove per-extension dependency install
Code packages all the dependencies using webpack for each extension so
there are no dependencies to install.
* Include source maps
I also moved this to its own patch because it feels sufficiently
standalone.
Fixes#5026.
* Refresh language patch
The base is slightly different so it needed to be refreshed.
* Add missing package.json
This was caused by switching to Code's package step which does not
include the package.json.
Fixes#5019.
* Include keytar
It seems this actually is used now.
