Automatically activate terminals created by the user when not using the Python command

https://github.com/Microsoft/vscode/issues/46192

This world allow us to automatically activate environments.

Use the following event:

const myTerm = createTerminal();
window.onDidOpenTerminal(t => {
  if (t !== myTerm) {
    // do stuff here
  }
});

[qubitron]

I was extrapolating from my own experience that a polyglot developer that only uses Python for a part of their app would be annoyed that we always activate Python in the terminal and we don’t have an easy way to say “create me a terminal without python”. At the same time, many people have asked to automatically activate Python in the terminal (or are confused when it doesn’t happen).

Thinking more about it… more would probably benefit from a default activated terminal than would be annoyed, so it’s probably better tradeoff to type “deactivate” when you don’t want the activated python terminal. In case it really disrupts people’s workflows or causes issues, we can add an option to disable the feature and they can fall back to using the “Python: Create Terminal” command.

[DonJayamanne]

This issue is used to discuss automatically performing action X, your issues is performing action X doesn't work. I.e. they are completely separate issues and best discussed separately without adding noise to this issue that would just confuse others.