Some presubmits can be take orders of magnitude longer than others, but
finding these presubmits is difficult if the time is printed at the end
of the output lines. Moving the time to the start, with enough alignment
for all plausible times, makes scanning the output easy.

Bug: 1309977
Change-Id: I9ba1a599e9825801e1128844a39c7ccafe046f91
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3744130Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>