[openssl/openssl] 2b9e2a: fuzz: make post handshake reachable

[Catena cyber]

  Branch: refs/heads/master
  Home:   https://github.com/openssl/openssl
  Commit: 2b9e2afc382490592078cdb69d06f54f0fefd4c6
      https://github.com/openssl/openssl/commit/2b9e2afc382490592078cdb69d06f54f0fefd4c6
  Author: Philippe Antoine <p.antoine at catenacyber.fr>
  Date:   2023-02-08 (Wed, 08 Feb 2023)

  Changed paths:
    M ssl/record/methods/tls_common.c
    M ssl/ssl_sess.c
    M ssl/statem/extensions_srvr.c
    M ssl/statem/statem_lib.c

  Log Message:
  -----------
  fuzz: make post handshake reachable

So that CVE-2021-3449 can be found through fuzzing

Reviewed-by: Paul Dale <pauli at openssl.org>
Reviewed-by: Kurt Roeckx <kurt at roeckx.be>
(Merged from https://github.com/openssl/openssl/pull/20128)