[VRF]Fixing vrf orch to update state_db when evpn nvo arrives late

[dgsudharsan]

What I did
Update state_db VRF_OBJECT table when there is update flow in the Vrf.
Since there is no EVPN nvo the addOperation returns here without updating state_db

https://github.com/sonic-net/sonic-swss/blob/2e6c5b209d575f73b867de9f3e56b3be4066acec/orchagent/vrforch.cpp#L114

However later when evpn nvo arrives there is no subsequent update operation.

This will result in removal message not getting processed due to the check in vrfmgrd

https://github.com/sonic-net/sonic-swss/blob/a821af0421de316555146615cffd4108ec566e20/cfgmgr/vrfmgr.cpp#L208

May  4 03:37:49.578686 r-anaconda-51 INFO swss#orchagent: :- updateVrfVNIMap: VRF 'Vrf1' vni 500200 old_vni 0
May  4 03:37:49.578701 r-anaconda-51 NOTICE swss#orchagent: :- updateVrfVNIMap: updateVrfVNIMap unable to find EVPN VTEP
May  4 03:37:49.578999 r-anaconda-51 INFO swss#orchagent: :- addOperation: VRF 'Vrf1' vni 500200 modify
May  4 03:37:49.579009 r-anaconda-51 INFO swss#orchagent: :- updateVrfVNIMap: VRF 'Vrf1' vni 500200 old_vni 0
May  4 03:37:49.579009 r-anaconda-51 INFO swss#orchagent: :- updateVrfVNIMap: addL3VniStatus vni 500200 vlan 0
May  4 03:37:49.579028 r-anaconda-51 INFO swss#orchagent: :- updateVrfVNIMap: VRF 'Vrf1' vni 500200 map update
May  4 03:37:49.579081 r-anaconda-51 NOTICE swss#orchagent: :- addOperation: VRF 'Vrf1' was updated

Why I did it
The update is missed when VRF is created and vni is set on the VRF but EVPN nvo arrives late.

How I verified it
Added UT to verify the flow

Details if related