fix(appset): add applicationset leader election to roles and clean up (#14369)

[rumstead]

fixes #14369

❯ k get lease
No resources found in argocd namespace.

❯ kgp | grep applicationset | wc -l
       0

❯ k scale deployment argocd-applicationset-controller --replicas=3
deployment.apps/argocd-applicationset-controller scaled

❯ k get lease
NAME                                   HOLDER                                                                                   AGE
58ac56fa.applicationsets.argoproj.io   argocd-applicationset-controller-6d4989d77f-4g4kk_aad428ab-e497-4572-b3bf-b0468bfad71e   9s

❯ k delete pod argocd-applicationset-controller-6d4989d77f-4g4kk
pod "argocd-applicationset-controller-6d4989d77f-4g4kk" deleted

❯ k get lease
NAME                                   HOLDER                                                                                   AGE
58ac56fa.applicationsets.argoproj.io   argocd-applicationset-controller-6d4989d77f-dqx2p_aa0bd163-f747-4cfd-af72-6cacbeaa638f   60s

Checklist:

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[bunnyshell]

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[rumstead]

I am confused why the applicationset controller needs get, list, watch for deployments. I removed it but can add it back.

[gdsoumya]

Agreed, I checked these permissions have been there from the very beginning but couldn't find any usage of these perms in the appset code so far.

[rumstead]

Leader election no longer requires config maps - kubernetes-sigs/controller-runtime#1773

[rumstead]

I don't think the applicationset controller needs any config map perms now?

[gdsoumya]

some appset plugin generator still needs access to configmaps eg.

argo-cd/applicationset/generators/plugin.go

Line 86 in 30a0088

cm, err := g.getConfigMap(ctx, generatorConfig.ConfigMapRef.Name)

[gdsoumya]

But I don't see any need for write perms in the code too, so this should be fine

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.21%. Comparing base (d2b881a) to head (ff31957).
⚠️ Report is 784 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #23976      +/-   ##
==========================================
+ Coverage   60.18%   60.21%   +0.02%     
==========================================
  Files         346      346              
  Lines       59276    59276              
==========================================
+ Hits        35676    35692      +16     
+ Misses      20740    20726      -14     
+ Partials     2860     2858       -2     

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