Gateway API v1.0 Support

[solmonk]

Gateway API v1.0 is officially GA. We need to figure out what is missing in our implementation, and action accordingly.

• Blog
• Release Notes
• Implementer's Guide

Important action items:

• Upgrade Gateway API dependency
• Update GatewayClass resource status - need to implement SupportedVersion condition.
• Update GatewayClass resource status - need to provide supportedFeature field.
• Revisit conformance test (requires finishing resource status update work). Based on conformance we should determine what to populate in supportedFeature field.
• Remove CRD installation from deployment / helm chart - This is an official guideline now. For our own CRDs, we might want to provide a separate installation instruction to each resource.

[solmonk]

• Dependency upgrade is done Upgrade gateway-api@v1.0.0 / controller-runtime@v0.16.3 #503
• CRD installation is kept for now, but new CRDs will not be included in the future release.
• GWClass resource status should be tracked as a bigger conformance milestone.