Start with/without debugging fails if Solution Explorer has never been opened

[zooba]

If you have Solution Explorer hidden, restart VS, open a standalone Python file (don't open any projects/solutions), and try and run with/without debugging you will get an E_FAIL error.

This is because we try and access the current solution before it exists. StartScriptCommand.cs should handle this case and continue as for when the solution is empty.

The workaround is to open Solution Explorer, which will initialize an empty solution.