`path` update does not always propagate

The system `path` is updated when we install an admin SDK. We also try to update the `process.env` and VS Code process environment. For some reason, based on https://github.com/dotnet/vscode-dotnet-runtime/issues/2379, it doesn't get updated until vscode restarts.

Older child processes of vscode may be the root cause of this, because their environment does not get updated - if that's the case, there's not much more we can do besides increase visibility on the button to restart vscode. Another issue may be that a change to the path is not causing the cache to update itself.