WIP: feat: Support metrics for GatewayAPI objects

[mrueg]

What this PR does / why we need it:
GatewayAPI is becoming more popular and kube-state-metrics should support providing metrics and insights into it.
This should be disabled by default, and only enabled when the cluster admin wants to use it.
I expect this to be used in a lot of clusters in future, when Ingress is becoming deprecated.

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)
New metrics for

• GatewayClass
• Gateway
• HTTPRoute
• TLSRoute

Not planned right now:

• TCPRoute
• UDPRoute

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #2449

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This pull-request has been approved by: mrueg

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PR needs rebase.

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