Re-evaluate what we consider to be an Enforced DNS policy

[maksymvavilov]

follow up on #586

Currently, the enforced condition is based on the Ready status of DNS Records that are affected by the DNS Policy. This leaves two possibilities for us to be misinformed:

1. The DNS Record CR is absent but the record is present in the provider - we will believe that the policy is not enforced when, de facto, it is.
2. The listener on the Gateway CR is not in a healthy state or misconfigured. The DNS Record is present and ready, but due to errors on the listener, it is not functional. We will get a false positive. This issue is created to implement a better solution to determine the enforced condition on the DNS Policy if that proves to be feasible