[EXPORTER] exporter endpoint doesn't support ipv6

[marcalff]

Discussed in #3056

^{Originally posted by qusijun September 9, 2024}
now, UrlParser can't parse ipv6 correctly , do we have the plan to support ipv6?

[marcalff]

The URL parser just looks for a : character in a url, it will be very confused when parsing IPv6 addresses.

https://github.com/open-telemetry/opentelemetry-cpp/blob/main/ext/include/opentelemetry/ext/http/common/url_parser.h