Change help text from Select Interpreter quick pick to say "Type to filter"

[brettcannon]

The current text is repetitive with the title of the quick pick being "Select Interpreter" and the help text saying, "Selected Interpreter: ...". There's also a question of whether telling users what the currently selected interpreter happens to be is useful since if they re-select the same interpreter, it doesn't harm anything.

[karrtikr]

Closing in favor of #19904.