[autotest] Make SERVER_JOB failures dedupe better by excluding the build name from the anchor

Remove build and suite name from the test name that used to form anchor when
deduping server job failure.

BUG=chromium:310148
TEST=unitest, test with bug filing:
./run_suite.py --build=trybot-lumpy-paladin/R33-4997.0.0-b1385  --board=lumpy
--suite_name=dummy -f True
old behavior:
https://code.google.com/p/autotest-bug-filing-test/issues/detail?id=1883

new behavior:
https://code.google.com/p/autotest-bug-filing-test/issues/detail?id=1880

Change-Id: I41ad7405aaca3fd5d99cae1bcc1b7ed58fda6e8e
Reviewed-on: https://chromium-review.googlesource.com/175623
Tested-by: Dan Shi <dshi@chromium.org>
Reviewed-by: Prashanth B <beeps@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
5 files changed