Remove toolchain_tests from the report.

We don't use that suite anymore. So, remove it from the
report. It was causing an exception.

BUG=None
TEST=Generated report without any issues.

Change-Id: Ie1c42b47a53e4d6e8a2665fdfba91d8d2ac963dc
Reviewed-on: https://chromium-review.googlesource.com/511866


Commit-Ready: Luis Lozano <llozano@chromium.org>
Tested-by: Luis Lozano <llozano@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>