ssa: HPA drift detection is broken on Kubernetes 1.26

[stefanprodan]

When changing the HPA version in tests from v2beta2 to v2, the drift detections fails by reporting drift even if the object didn't changed. We need to update SSA to client-go 1.26 and figure out how to deal with the Kubernetes API bug (the workaround put in place for v2beta2 doesn't seem to work for v2).

[hiddeco]

Context around previous addressing of issue in #207

[aryan9600]

i tried to reproduce this on a 1.26 cluster created using kind and was unable to, there's no difference outputted when i run kubectl diff --server-side -f hpa.yaml and no drift is reported in the kustomize-controller logs with reconciliation progressing normally as it should.

❯ k logs -f -n flux-system kustomize-controller-64bd85bd5f-wpbcj
{"level":"info","ts":"2023-01-11T06:50:27.194Z","msg":"server-side apply completed","controller":"kustomization","controllerGroup":"kustomize.toolkit.fluxcd.io","controllerKind":"Kustomization","Kustomization":{"name":"podinfo","namespace":"flux-system"},"namespace":"flux-system","name":"podinfo","reconcileID":"9c2b509f-21e6-4278-bb1f-5a2dd69de59c","output":{"Deployment/default/podinfo":"created","HorizontalPodAutoscaler/default/podinfo":"created"," Service/default/podinfo":"created"},"revision":"master/fdd0a0b7dad56fbc6bb71e7e8badee5a3a3c663f"}
{"level":"info","ts":"2023-01-11T06:50:27.226Z","msg":"Reconciliation finished in 147.578915ms, next run in 5m0s","controller":"kustomization","controllerGroup":"kustomize.toolkit.fluxcd.io","controllerKind":"Kustomization","Kustomization":{"name":"podinfo","namespace":"flux-system"},"namespace":"flux-system","name":"podinfo","reconcileID":"9c2b509f-21e6-4278-bb1f-5a2dd69de59c","revision":"master/fdd0a0b7dad56fbc6bb71e7e8badee5a3a3c663f"}
{"level":"info","ts":"2023-01-11T06:55:26.545Z","msg":"server-side apply completed","controller":"kustomization","controllerGroup":"kustomize.toolkit.fluxcd.io","controllerKind":"Kustomization","Kustomization":{"name":"podinfo","namespace":"flux-system"},"namespace":"flux-system","name":"podinfo","reconcileID":"a4338a44-5312-402a-baf4-cea5545aafe2","output":{"Deployment/default/podinfo":"unchanged","HorizontalPodAutoscaler/default/podinfo":"unchanged","Service/default/podinfo":"unchanged"},"revision":"master/fdd0a0b7dad56fbc6bb71e7e8badee5a3a3c663f"}
{"level":"info","ts":"2023-01-11T06:55:26.560Z","msg":"Reconciliation finished in 109.120046ms, next run in 5m0s","controller":"kustomization","controllerGroup":"kustomize.toolkit.fluxcd.io","controllerKind":"Kustomization","Kustomization":{"name":"podinfo","namespace":"flux-system"},"namespace":"flux-system","name":"podinfo","reconcileID":"a4338a44-5312-402a-baf4-cea5545aafe2","revision":"master/fdd0a0b7dad56fbc6bb71e7e8badee5a3a3c663f"}

Events:
  Type    Reason       Age    From                  Message
  ----    ------       ----   ----                  -------
  Normal  Progressing  9m37s  kustomize-controller  Service/default/podinfo created
Deployment/default/podinfo created
HorizontalPodAutoscaler/default/podinfo created
  Normal  ReconciliationSucceeded  9m37s  kustomize-controller  Reconciliation finished in 147.578915ms, next run in 5m0s
  Normal  ReconciliationSucceeded  4m38s  kustomize-controller  Reconciliation finished in 109.120046ms, next run in 5m0s