[OpenSIPS-Devel] [OpenSIPS/opensips] 397ef8: Fix computing the size to clone for a body part

[Bogdan Andrei IANCU]

  Branch: refs/heads/master
  Home:   https://github.com/OpenSIPS/opensips
  Commit: 397ef8fe1e300df533cd7b7d1322fc99b4011cd8
      https://github.com/OpenSIPS/opensips/commit/397ef8fe1e300df533cd7b7d1322fc99b4011cd8
  Author: Bogdan-Andrei Iancu <bogdan at opensips.org>
  Date:   2023-06-27 (Tue, 27 Jun 2023)

  Changed paths:
    M parser/parse_body.c

  Log Message:
  -----------
  Fix computing the size to clone for a body part

Take the optional header len into account also when cloning a body part struct.
This particular bug occured when using add_body_part() with extra hdr parameter in conjunction with an async() operation (or failure route)
Credits for reporting and helping with repoducing this go to @thuroc
Fixes #3067

(cherry picked from commit a042588e322c5acf997313773cbc5ff6e007c956)