Previously, we only returned the first result that looked like an IPv6
or IPv4 address.
This cropped up when attempting to connect to https://cxbyte.me/ whilst
IPv6 on the server wasn't working. Since we only returned the first
result, which happened to be the IPv6 address, we wasn't able to
connect.
Returning all results allows curl to attempt to connect to a different
IP if one of them isn't working, and potentially make a successful
connection.
Previously, we would stop the repeat timer even if we got a null result.
This caused the pending lookup to:
- Never resolve, and
- Never get purged for too many retries
I believe the underlying issue is something on the socket level, but we
should handle this case regardless.
...and make sure it will eventually complete (or fail) by adding a
timeout retry sequence.
Fixes an issue where RequestServer would stick around after exit,
waiting for piled up DNS requests for a long time.