Remove IntraNought gateway from new routers

Summary:
Remove gateway 172.27.27.1 from Intranought on router-002 and router-003
to avoid having 2 default routes (one for Public and one for IntraNought)
and then some network issues.

Reviewers: dereckson, Duranzed

Reviewed By: dereckson

Subscribers: Duranzed, dereckson

Differential Revision: https://devcentral.nasqueron.org/D4035