MiniTerm: ProcessFactory.Start is hard-coded to run "cmd.exe" and ignores intended parameter

[oising]

See:

https://github.com/Microsoft/console/blob/34ff272cfa5b49dcb0bbe7aaec41797d9c285e5e/samples/ConPTY/MiniTerm/MiniTerm/Processes/ProcessFactory.cs#L21

[zadjii-msft]

Huh. That does look wrong to me. Would love to review a PR :)

[oising]

There are a few other things that need reshaping. I'll see what I can do.