Update logic to when we show the Install Python (Extension) commands

[IanMatthewHuff]

Per feedback from @rchiodo. We can better update the logic for the new Install Python and Install Python Extension commands. In particular we should show the extension install command even if we happen to pick up a global python kernel via our interpreter search.

This is better logic than the old dummy kernel logic for this situation as this customer wouldn't realize before that there was a way to get more python kernels if they happened to have some globally accessibly python jupyter kernels already installed.