[Test Gap][<Vlan>][<T0:>]<Vlan interface should be up when all member ports are oper down>

[prsunny]

Test Gap Description

Ensure Vlan interface stays up when all member ports are oper down.

Test Plan

Bring down all member ports of Vlan
Ensure Vlan Interface stays up 'show ip interface'
Ensure BGP advertisements of Vlan subnet (IPv4 and IPv6)
Validate IPIP decap

Test environment

All T0 SKUs

Attach files (if any)

No response