[autotest] ignore import error from selenium

Ignore import error, as this can happen when builder tries to call the setup
method of test that imports chromedriver.

BUG=None
TEST=None

Change-Id: Icf60e05cba11031746030cd6ce50e7d5cf31eda1
Reviewed-on: https://chromium-review.googlesource.com/177341
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
Tested-by: Dan Shi <dshi@chromium.org>
1 file changed