Revert "Fail fast during advanced networking test"

This reverts commit ae3dbdc11fc182109ca07253b0d81183321d7f1c.

Commit ae3dbdc11fc182109ca07253b0d81183321d7f1c was seen as the recent spike for
the "ssh timeout" failures in neutron, as referenced by this bug [1]. With this
revert, we hope to get things moving again while we root cause the other issue.
We will re-submit ae3dbdc11fc182109ca07253b0d81183321d7f1c to continue
debugging as well.

[1] https://bugs.launchpad.net/bugs/1323658

Change-Id: Ida6e1d2096673d359ac7a8eaf9ab366e056c56f5
Merge "Revert "Fail fast during advanced networking test""