engine: forcing an update should also force a pod update. Fixes https://github.com/tilt-dev/tilt/issues/1928

[nicks]

Hello @jazzdan, @maiamcc,

Please review the following commits I made in branch nicks/ch4742:

7cf255f (2020-06-05 17:35:16 -0400)
engine: forcing an update should also force a pod update. Fixes #1928

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[nicks]

This is obviously a very simple solution to a pretty complex problem.

Hitting the "force update" button will replace the existing pods, even if they haven't changed. I think this is closer to what most people expect from this button, based on the feedback I've heard and Maia's discussion here: #1928 (comment)

I still think there's value in more full-featured solutions, but this has been outstanding for so long, I'm hoping that this will fix 90% of the problems