[curl] Added http3 feature

[wkornewald]

This enables HTTP/3 with ngtcp2, nghttp3 and OpenSSL. The other HTTP/3 options (not based on ngtcp2) are experimental according to this page: https://curl.se/docs/http3.html

Tested the resulting build with curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_3ONLY) and CURLOPT_VERBOSE and Wireshark to confirm that HTTP/3 is actually working.

• Changes comply with the maintainer guide.
• SHA512s are updated for each updated download.
• The "supports" clause reflects platforms that may be fixed by this new version.
• Any fixed CI baseline entries are removed from that file.
• Any patches that are no longer applied are deleted from the port's directory.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is added to each modified port's versions file.

[talregev]

Duplicate to my PR #46459

[wkornewald]

I see, then I'll better close this.