Fix dns_managed_zone tests using unverified domain

[modular-magician]

fixes #13944

Per the issue, tf-test.club is not dedicated to our organization, but gcp.tfacc.hashicorptest.com is. For that reason, we chose only to verify gcp.tfacc.hashicorptest.com for these test projects, and the tests can use that domain instead.

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Derived from GoogleCloudPlatform/magic-modules#7422

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