Gateway API `SupportedFeatures` field

[mlavacca]

Problem Statement

GatewayClass's SupportedFeatures field graduation is one of the targets for Gateway API 1.2 (https://github.com/kubernetes-sigs/gateway-api/issues/3164). The main point of such a feature is adding a new SupportedFeatures field in the GatewayClass that is populated by the implementation. Such a field has two main purposes:

• allow the conformance suite to read the GatewayClass and run the needed tests, without the need from the implementation maintainer to manually specify which features are supported
• give users feedback on the features currently implemented by the implementation.

Additional Information

https://github.com/kubernetes-sigs/gateway-api/pull/3200 introduced a breaking change in the feature, so we need to wait for the next release (1.2) to be able to properly implement it.

Acceptance Criteria

• [ ] The SupportedFeatures field is supported by the operator

[mlavacca]

This is blocked by the Gateway API 1.2 release