Conda is not currently being used during test runs

[rchiodo]

We really need to run some or all of our tests in a conda environment.

This would have caught these two issues at the very least:
https://github.com/microsoft/vscode-python/issues/9437
#9439

I think we'd just have another machine with conda and say linux 3.7 as a minimum

[rchiodo]

I think the DS team could also do this work.

[DonJayamanne]

We have UI tests that test running files and code in terminal.
However I don't think we're using those tests anymore.

[DonJayamanne]

We have UI tests for these, here they are https://github.com/microsoft/vscode-python/blob/master/uitests/features/interpreter/terminal.feature

[karrtikr]

Seeing as we have not seen such conda issues for a while, marked it as a needs decision to discuss whether we still need it.

[DonJayamanne]

Since we've moved the Jupyter extension into a seprate repo, i think we can close this for now.