Update dreamhost to use dns-list_records instead of domain-list_domains

[ryan953]

The Dreamhost api command domain-list_domains will be retired on Nov 2nd 2021.

This diff converts the _authenticate() method to use dns-list_records instead.

Fixes #974

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The obvious difference between domain-list_domains and dns-list_records is that list_records will return any A, CNAME, MX, TXT (and so on) record in the Dreamhost account. Potentially a lot more information compared to the list of domains.

Using the test api token (scroll to "Test Account") we can see the difference in response size:

Before:

$ curl -so /dev/null "https://api.dreamhost.com/?key=6SHU5P2HLDAYECUM&cmd=domain-list_domains&format=json"  -w '%{size_download}'
752

After:

$ curl -so /dev/null "https://api.dreamhost.com/?key=6SHU5P2HLDAYECUM&cmd=dns-list_records&format=json"  -w '%{size_download}'
15940

This is just an example account but illustrates the difference. Any account could have a large number of domain, and/or a large number of records per domain.

I added the condition that the found record should be of type "A" or "AAAA". It's trivial for someone to add any domain (like facebook.com) to their account and create that record though. Doing so puts facebook.com in both the responses for both dns-list_records and domains-list_domains. I can see that behavior today in my account.
This means that _authenticate() wasn't, and still doesn't, do a strong ownership check of the domain name. Instead is does verify that the api token works. We shouldn't need that ownership check though, because if nameservers point somewhere else nothing will read that dns record.

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The notice about all the deprecated Dreamhost API's is here, but it's likely to change after Nov 2nd. Copied here for reference:

Upcoming EOL

As of November 2, 2021, the following API commands will be removed and no longer function.

Account API commands
Domain API commands
Mail API commands
MySQL API commands
Rewards API commands
User API commands
The following three commands will continue to function normally.

Announcement List API commands
API metacommands
DNS API commands

[adferrand]

Thanks, I prepare a release right now.