Address and Listener Status in Gateways

[shaneutt]

Problem Statement

When we first built the POC we didn't bother much with statuses for objects, we just focused on the high level demo bits. As such we still need to properly implement the address and listener status for Gateway resources.

Acceptance Criteria

• Gateway resource status addresses and listener status should be updated properly according to Gateway API specification
• an integration test should be added that verifies the status for multiple Gateway resources with different configurations