Fix vpn scenario test to work with DVR

IPSec is deployed in SNAT router in case of DVR,
to make it work for instances with floating IPs we
need to add extra routes to neighbour subnet via SNAT.

Related-Prod: PRODX-29188
Change-Id: I191591db2499a45ab8d00238da1fe7403c96915d
(cherry picked from commit 100a633392f06b49419a14cc972a2096e1962930)
(cherry picked from commit a19b5f85401b1070203f3c1d29d20efd1a7e54ce)
1 file changed