Brian Cunnie 09249be0a0 CI: don't double-count the nameservers ...

On macOS, `whois` returns _two_ results for the domain `sslip.io` from
two different whois servers:

- whois.nic.io
- whois.namecheap.com

This means that every nameservers is double-counted. To fix, we remove
the duplicates.

fixes:
```
     Failure/Error: expect(dig_nameservers.sort).to eq(whois_nameservers.sort)

       expected: ["ns-aws.nono.io.", "ns-aws.nono.io.", "ns-azure.nono.io.", "ns-azure.nono.io.", "ns-gce.nono.io.", "ns-gce.nono.io."]
            got: ["ns-aws.nono.io.", "ns-azure.nono.io.", "ns-gce.nono.io."]

       (compared using ==)
     # ./spec/check-dns_spec.rb:44:in `block (3 levels) in <top (required)>'
```

2020-12-01 09:22:24 -08:00

..

check-dns_spec.rb

CI: don't double-count the nameservers

2020-12-01 09:22:24 -08:00