chrome/browser/ui/views/webauthn: tighten two-line hover buttons.

At the request of UX, reduce the amount of spacing between the two lines
of text and distribute it to the top and bottom of the HoverButton.

Screenshot of account selection:
https://screenshot.googleplex.com/troBdpwEOrT.png

Screenshot of (unchanged) transport list:
https://screenshot.googleplex.com/ZeqLqJ9GWja.png

Change-Id: I3d8470f51cde6051805b258aac2c79dca8b11b2f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1622472
Commit-Queue: Adam Langley <agl@chromium.org>
Commit-Queue: Nina Satragno <nsatragno@chromium.org>
Auto-Submit: Adam Langley <agl@chromium.org>
Reviewed-by: Nina Satragno <nsatragno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661849}
1 file changed