Basic DNSPolicy in a single cluster context

[mikenairn]

High level tasks relating to https://github.com/Kuadrant/architecture/pull/30

• [x] https://github.com/Kuadrant/multicluster-gateway-controller/issues/496
• [x] https://github.com/Kuadrant/multicluster-gateway-controller/issues/311
• [x] https://github.com/Kuadrant/multicluster-gateway-controller/issues/646
• [x] https://github.com/Kuadrant/multicluster-gateway-controller/issues/655

Follow Up: https://github.com/Kuadrant/architecture/issues/67

[maleck13]

Removed the provider ref change into its own epic https://github.com/Kuadrant/multicluster-gateway-controller/issues/715

[maleck13]

Follow up to this epic https://github.com/Kuadrant/multicluster-gateway-controller/issues/716 additional improvments