[stable/nginx-ingress] Daemonset annotation should not be set by default

[ChiefAlexander]

Describe the bug

helm template --set controller.kind=DaemonSet ./nginx-ingress | kubeval
The document stdin contains an invalid DaemonSet
---> spec.template.metadata.annotations: Invalid type. Expected: object, given: null

The annotations field of the daemonset should be ignored if it is nil

Version of Helm and Kubernetes: v2.13.1

Which chart: nginx-ingress

What happened: Chart is invalid

What you expected to happen: Chart to be valid

How to reproduce it (as minimally and precisely as possible):

helm template --set controller.kind=DaemonSet ./nginx-ingress | kubeval

Anything else we need to know:

[ChiefAlexander]

Found while looking into #12961

[ChiefAlexander]

/assign