[autotest] Remove Milestone from automatic bugs.

This cl also does:
1. Cleanup: removed the old tracker completely, since we've been
    using phapi for ~ a month and things are fine.
2. Fixes unittest: New unittest only verify basic control flow
    for filing a new issue/deduping an issuei, since the core bug
    filer is dependent on several external modules and a functional
    test on a fake project is far more effective than unittests.

TEST=Ran a suite and filed/deduped bugs.
BUG=chromium:267560, chromium:271070

Change-Id: I5e238d647608c8321f4308eede309d58b94ab3a3
Reviewed-on: https://gerrit.chromium.org/gerrit/65551
Tested-by: Prashanth Balasubramanian <beeps@chromium.org>
Reviewed-by: Fang Deng <fdeng@chromium.org>
Commit-Queue: Prashanth Balasubramanian <beeps@chromium.org>
4 files changed