doc: fix broken link in http2.md

PR-URL: #35112
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ricky Zhou <0x19951125@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Derek Lewis <DerekNonGeneric@inf.is>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

Author: Trott

doc/api/http2.md

@@ -3725,7 +3725,7 @@ you need to implement any fall-back behaviour yourself.
 [`ClientHttp2Stream`]: #http2_class_clienthttp2stream
 [`Duplex`]: stream.html#stream_class_stream_duplex
 [`Http2ServerRequest`]: #http2_class_http2_http2serverrequest
-[`Http2ServerResponse`]: #class-http2http2serverresponse
+[`Http2ServerResponse`]: #http2_class_http2_http2serverresponse
 [`Http2Session` and Sockets]: #http2_http2session_and_sockets
 [`Http2Stream`]: #http2_class_http2stream
 [`ServerHttp2Stream`]: #http2_class_serverhttp2stream