[R2.0-Build 12]: ping to outside network not going thro with policy with service instance

test scenarios:

- VN 'public' (10.204.220.192/29) and VN 'vnet1' (9.9.9.0/24) connected with policy(via transparent firewall)
- policy allows all traffic between these VNs
- route target(64512:20001) is added in vnet1. so default route(0.0.0.0/0) leaked in vnet1 and public, as expected
- now ping from public(10.204.220.192/29) VN's VM to outside should go through but it fails.

ping between public and vnet1 is working as expected.

Naveen has debugged the issue and found that VRF
default-domain:SecurityGroupRegressionTests7-31434507:vnet1:service-898e40eb-b772-4c4d-ae79-d331a27f8ff6-default-domain_SecurityGroupRegressionTests7-31434507_si_trans_firewall doesn't have route 0/0 because it doesn't have route import target:64512:20001.

for target:64512:2000 grp list, please check snapshot attached.

setup info:

env.roledefs = {
    'all': [host1,host2,host3,host4,host5],
    'cfgm': [host1,host2,host5],
    'openstack':[host2],
    'control': [host2,host1],
    'compute': [host3,host4],
    'collector': [host2,host1],
    'webui': [host1],
    'database': [host1,host2,host5],
    'build': [host_build],
}

env.hostnames = {
    'all': ['nodec64', 'nodeg18', 'nodeh8', 'nodec11', 'nodec12']
}