Add GroupChangeLog feature gate to fix es indexing cardinality

[94DanielBrown]

Tested in kind

FYI I got error when using flux install to test

[kind-kind|flux-system] ➜  flux-bootstrap git:(main) ✗ k logs kustomize-controller-6d8bf96598-4t595                                                                                                                    [dev/flux-bootstrap]
{"level":"error","ts":"2025-02-12T15:55:13.993Z","logger":"setup","msg":"unable to start manager","error":"failed to determine if *v1.Kustomization is namespaced: failed to get restmapping: unable to retrieve the complete list of server APIs: kustomize.toolkit.fluxcd.io/v1: no matches for kustomize.toolkit.fluxcd.io/v1, Resource="}

But installing with this worked fine as crd was v1 not v1beta2
k apply -f https://github.com/fluxcd/flux2/releases/latest/download/install.yaml

example logs from applying kustomization after

{“level":"info","ts":"2025-02-12T17:20:23.527Z","msg":"server-side apply for cluster definitions completed","controller":"kustomization","controllerGroup":"kustomize.toolkit.fluxcd.io","controllerKind":"Kustomization","Kustomization":{"name":"podinfo","namespace":"flux-system"},"namespace":"flux-system","name":"podinfo","reconcileID":"c78a46e3-5d45-4c01-8cfa-87ed9cf93e3a","output":{"unchanged":["Service/default/podinfo","Deployment/default/podinfo","HorizontalPodAutoscaler/default/podinfo”]}}

[stefanprodan]

Please remove this and add a feature flag called GroupedChangelog here: internal/features/features.go, also please use this name in all code instead of EsLogging.

[94DanielBrown]

Updated and tested
{"level":"info","ts":"2025-02-13T12:07:31.518Z","logger":"setup","msg":"loading feature gate","GroupChangeLog":true}

[stefanprodan]

This refers to the kustomize-controller version, should be v1.5

[94DanielBrown]

ah sorry, fixed

[stefanprodan]

@94DanielBrown can you please squash all commits into one, then I can merge. Thanks!

[stefanprodan]

@94DanielBrown can you please signoff you commit

[stefanprodan]

@94DanielBrown see here how to signoff on the commit https://github.com/fluxcd/kustomize-controller/pull/1361/checks?check_run_id=37178702532

[stefanprodan]

LGTM

Thanks @94DanielBrown 🏅

[stefanprodan]

Final step is to document the feature gate here: https://github.com/fluxcd/website/blob/main/content/en/flux/components/kustomize/options.md#feature-gates