[autotest] Add an option in frontend to force a new job requires server-side packaging

BUG=chromium:453624
TEST=rebuild AFE, try to create new jobs with require ssp enabled/disabled.
DEPLOY=afe
CQ-DEPEND=CL:249841

Change-Id: I1692c9af794b57fca976fd289fbd3606eb19e504
Reviewed-on: https://chromium-review.googlesource.com/256404
Reviewed-by: Dan Shi <dshi@chromium.org>
Tested-by: Dan Shi <dshi@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
4 files changed