Unit Tests: limit warnings, fix racing

[kuritka]

This PR is part of a larger whole, where I want to promote dependencies and controller-gen in order to be able to fix unintentional loops, when GSLB or Ingress annotation changes.

• One of the controller tests asserted two slices that were not sorted. Sometimes it happened that the compared slice was in a different order, so the assert failed. (https://github.com/k8gb-io/k8gb/compare/tests?expand=1#diff-cdaa5d8a2fd5599a082eb3ac57db11e206344930635e6f219e26f98e42d1f61aR584-R585)

• Test Dig default DNS (8.8.8.8.8) with fqdn sometimes timeouted. I fixed the timeout error with a test. (https://github.com/k8gb-io/k8gb/compare/tests?expand=1#diff-1b70ee441d18dc0d9e2e0665a5b61a3a3a5846a8ab7fe3aebb1637f8bf9bcf02R50-R53)

Controller tests generate a lot of warnings because the reconciliation does a dig into 127.0.0.1:7753. I wrap to FakeDNS so the dig goes through without warning.

utils.NewFakeDNS(fakeDNSSettings).
  Start().
  RunTestFunc(func() {
         // arrange
         // act
         // assert     
  })

Fixes #974

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[ytsarev]

Great stuff 👍