Clarify that using a custom jedi also means a custom parso (#11708)
Clarify that using a custom jedi also means a custom parso (#11708)

Even with a good understanding of both VSCode-Python and Jedi,
this is easy to overlook.
DonJayamanne/pythonVSCode,DonJayamanne/pythonVSCode,DonJayamanne/pythonVSCode,DonJayamanne/pythonVSCode,DonJayamanne/pythonVSCode