Allow for passing user defined annotations to the IngressClass resource template

[cparadal]

At the moment, it's not possible to pass user-defined/custom annotations to the IngressClass resource template. As can be seen here, the current template will only add an annotations stanza if the ingressClass is marked as default.

Our use case for the above is to be able to add ArgoCD related annotations, e.g. argocd.argoproj.io/sync-options: Prune=false to prevent resource pruning.

[k8s-ci-robot]

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