Fix all 'auto' imports in a file

[rchiodo]

Especially since this setting showed up:

    "python.analysis.addImport.heuristics": true,

I'd like to be able to fix all of the auto import issues in a file, much like Typescript has. Most of the time now I just pick the first item in the Add imports quick fix list.

[rchiodo]

Hmm, maybe this item is the same?
#2667