Change default active interpreter to point to the python in current path

[brettcannon]

As a notice user I test & run Python (& or Jupyter) with python thats in my current path.
However when using Python or Jupyter notebooks a different Python interpreter is used hence:
In Jupyter extension

• I get prompted to install ipykernel (no idea what this is, i'll click ok)
• After running a cell, i get module not found errors

Suggestion:
Change the active interpreter in the Python extnsion to point to what's in the current path.

Related issue in Jupyter is here microsoft/vscode-jupyter#5998
(We could either change Jupyter extension to use Python in path or optionally make this change in Python exension)

Originally posted by @DonJayamanne in a discussion

[brettcannon]

The problem I see with this is what python points to changes every time you install Python. For instance, it might be CPython 3.9.4 today, but when I install CPython 3.9.5 and CPython 3.8.10 later in that order then python will point at Python 3.8 which also won't have ipykernel installed.

[brettcannon]

Moved to #17205

[DonJayamanne]

I believe this is now being addressed/tracked here #18178