Add an alternative "magic link sent" screen

[0nko]

This PR adds an alternative "magic link sent" screen, which will be used in WCAndroid A/B test for improving the login success rate.

[hichamboushaba]

@0nko just a suggestion, why not define the new fragment inside Woo directly? (I mean something similar to what we've done with other experiments, for example: https://github.com/woocommerce/woocommerce-android/pull/6891). I think this would allow moving faster with iterations.

[nbradbury]

@0nko Looks good and I'll approve it, but I'll hold off merging until you have a chance to respond to @hichamboushaba's suggestion.

[annchichi]

Heya @0nko, thanks for this!

I was looking for an illustration that fits the context here. I found the WooCommerce Admin has this letter illo, which may fit better, although the graph isn't that appealing. 😬

No 1 Is it possible to change this letter illustration? No 2 Happy to reuse the copy. But I wonder if we can do a slight tweaking so we won't have one word left in the 2nd sentence. We can push "Check your Spam or Junk Mail folder" to the second line. Asset link here.

[0nko]

Hey @annchichi, I've updated the UI:

[0nko]

@hichamboushaba I suppose you're right, I automatically assumed it needed to be done here. But since it's already finished I'd say let's keep it and I'll do it in WCAndroid next time.

cc: @nbradbury