helm chart support arg `fqdn-template`

[timlynch2k]

helm chart support for fqdn-template:

external-dns option fqdn-template can be configured with helm chart. additionally, all of the args identified in https://github.com/kubernetes-sigs/external-dns/issues/4260 can be configured via helm.

continue using helm:

neither this nor bitnami chart supports all of the args. bitnami's chart has more coverage, but does not support all of the ignore args.