gitlab.com and docs.gitlab.com need AAAA records

Problem: gitlab.com and docs.gitlab.com only return DNS records for IPv4 (A records).

Solution: Please add DNS entries for IPv6 (AAAA records).

Justification/explanation: This way, IPv6-enabled or IPv6-only hosts will not have to fall back to IPv4 and will not have to go through translation mechanism like NAT64 to reach these services.