[v2.13.0-rc2] ArgoCD is not working when plugin without discovery is configured

[pradithya]

Checklist:

• I've searched in the docs and FAQ for my answer: https://bit.ly/argocd-faq.
• I've included steps to reproduce the bug.
• I've pasted the output of argocd version.

Describe the bug
Many (if not all) applications registered in ArgoCD is incorrectly recognized as plugin application when a plugin without discovery functionality is configured.
The bug seems introduced by this PR #18053 . Specifically, this line of code in cmpSupports function.

To Reproduce

1. Install ArgoCD version v2.13.0-rc1 / rc-2
2. Create kustomize application, for example

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: bootstrap
  namespace: argocd
spec:
  project: default
  destination:
    name: in-cluster
    namespace: argocd
  source:
    repoURL: git@github.com:pradithya/argocd-hack.git
    targetRevision: main
    path: bootstrap
    kustomize: {}
  syncPolicy:
    automated: {}
    syncOptions:
    - ServerSideApply=true

3. Create CM plugin without discovery functionality configured
4. Check that the application above is somehow recognized as plugin app instead of kustomize app

Full repository to reproduce pradithya/argocd-hack@4ab374e

Expected behavior

application should be rendered properly and recognized as kustomize application instead of plugin application.

Screenshots

Version

2024/10/02 17:32:56 maxprocs: Leaving GOMAXPROCS=10: CPU quota undefined
argocd: v2.13.0-rc1+74a367d
  BuildDate: 2024-09-16T08:51:02Z
  GitCommit: 74a367d10e7110209610ba3ec225539ebe5f7522
  GitTreeState: clean
  GoVersion: go1.22.7
  Compiler: gc
  Platform: darwin/arm64
argocd-server: v2.13.0-rc2+0f083c9
  BuildDate: 2024-09-20T11:37:53Z
  GitCommit: 0f083c9e58638fc292cf064e294a1aa53caa5630
  GitTreeState: clean
  GoVersion: go1.23.1
  Compiler: gc
  Platform: linux/arm64
  Kustomize Version: v5.4.3 2024-07-19T16:40:33Z
  Helm Version: v3.15.2+g1a500d5
  Kubectl Version: v0.31.0
  Jsonnet Version: v0.20.0

Logs

Paste any relevant application logs here.