Ability to disable auto environment activation for different terminal profiles.

[LiamLombard]

Hey, first off great work, love the extension!

My request is pretty much as the title says, if I wanted to set up terminal profiles in vscode for non shell-like programs, for example a python repl (or any other sort of repl) the auto activation line is still attempted to be entered into the terminal, which can either show as an error or (what prompted me to make this feature request) get in the way of the terminal startup commands and cause issues.

My initial thought of a solution to this would be to add a setting which lets you list terminal profiles for which the autoactivation will not be run for. But I wouldn't be surprised if there were other ways to tackle this, which I leave to those with experience of this codebase to suggest.

I'm happy to actually write the code and submit a PR but it might be helpful to have some pointers of where to look.

Thanks!

[brettcannon]

Moved to #16998