Given the following configuration (see attached Postman for requests):

1. set IPv4 address on local0 interface
2. create sub-interface under a different interface
3. configure sub-interface as unnumbered ("use" interface local0)
4. read sub-interface operational data / VAT data

The sub-interface should have an IP address, but it doesn't. Note that regular interfaces work as expected.

Equivalent configuration through VAT:

1. ip_address_add_del sw_if_index 0 192.168.0.1/24
2. create_subif sw_if_index 1 sub_id 3 dot1ad
3. sw_interface_set_unnumbered sw_if_index 0 unnum_if_index 3
4. ip_address_dump ipv4 sw_if_index 3

[ {"ip": "192.168.0.1", "prefix_length": 24}]