Make storyboard/python26 jobs non-voting

Ie82c11c0c2138a89dae516508a37db6f2e0460b7 adds tests which will fail with
python26. Making these jobs non-voting until python26 is fixed in
storyboard.

Change-Id: Ic52cc644004fac3f9071e3b2fd63d7b132c6b76b