Fix bug GH-9356: Incomplete SAN validation of IPv6 address

IPv6 addresses are valid entries in subjectAltNames. Certificate
Authorities may issue certificates including IPv6 addresses ex

Fix bug GH-9356: Incomplete SAN validation of IPv6 address

IPv6 addresses are valid entries in subjectAltNames. Certificate
Authorities may issue certificates including IPv6 addresses except
if they fall within addresses in the RFC 4193 range. Google and
CloudFlare provide IPv6 addresses in their DNS over HTTPS services.

Internal CAs do not have those restrictions and can issue Unique
local addresses in certificates.

Closes GH-11145

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