Settings WebUI: Update spacing between buttons in settings box

BUG=911375

Change-Id: I91a98fb01833d2b6814b2aa4aaeeec0e5e624d71
Reviewed-on: https://chromium-review.googlesource.com/c/1374834
Commit-Queue: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616232}
1 file changed