feat: Add client-go metrics registration to operatorpkg

[jonathan-innis]

Issue #, if available:

Description of changes:

Add the ability to register client metrics with the RegisterClientMetrics() call.

When calling the metrics endpoint, we see the following output reflecting the updated metrics that are returned here -- which reflects the actual apiserver calls that are made (not hitting the controller-runtime cache)

client_go_request_duration_seconds_count{group="",kind="events",subresource="",verb="PATCH",version="v1"} 10
client_go_request_duration_seconds_count{group="",kind="nodes",subresource="",verb="DELETE",version="v1"} 12
client_go_request_duration_seconds_count{group="",kind="nodes",subresource="",verb="LIST",version="v1"} 1
client_go_request_duration_seconds_count{group="",kind="nodes",subresource="",verb="PATCH",version="v1"} 12
client_go_request_duration_seconds_count{group="",kind="pods",subresource="",verb="LIST",version="v1"} 1
client_go_request_duration_seconds_count{group="",kind="pods",subresource="eviction",verb="CREATE",version="v1"} 29
client_go_request_duration_seconds_count{group="",kind="services",subresource="",verb="GET",version="v1"} 1
client_go_request_duration_seconds_count{group="apps",kind="daemonsets",subresource="",verb="LIST",version="v1"} 1
client_go_request_duration_seconds_count{group="coordination.k8s.io",kind="leases",subresource="",verb="GET",version="v1"} 3
client_go_request_duration_seconds_count{group="coordination.k8s.io",kind="leases",subresource="",verb="LIST",version="v1"} 1
client_go_request_duration_seconds_count{group="coordination.k8s.io",kind="leases",subresource="",verb="UPDATE",version="v1"} 78
client_go_request_duration_seconds_count{group="karpenter.k8s.aws",kind="ec2nodeclasses",subresource="",verb="LIST",version="v1beta1"} 2
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodeclaims",subresource="",verb="CREATE",version="v1beta1"} 12
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodeclaims",subresource="",verb="LIST",version="v1beta1"} 1
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodeclaims",subresource="",verb="PATCH",version="v1beta1"} 24
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodeclaims",subresource="status",verb="PATCH",version="v1beta1"} 12
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodeclaims",subresource="status",verb="UPDATE",version="v1beta1"} 40
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodepools",subresource="",verb="LIST",version="v1beta1"} 1
client_go_request_duration_seconds_count{group="karpenter.sh",kind="nodepools",subresource="status",verb="PATCH",version="v1beta1"} 14
client_go_request_duration_seconds_count{group="policy",kind="poddisruptionbudgets",subresource="",verb="LIST",version="v1"} 1
client_go_request_duration_seconds_count{group="storage.k8s.io",kind="csinodes",subresource="",verb="LIST",version="v1"} 1

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