[dovecot/core] 665a20: lib-oauth2: Add missing content-type header

[GitHub]

  Branch: refs/heads/master-2.2
  Home:   https://github.com/dovecot/core
  Commit: 665a2083e3b53f38398cccf173d197e22a405d99
      https://github.com/dovecot/core/commit/665a2083e3b53f38398cccf173d197e22a405d99
  Author: Aki Tuomi <aki.tuomi at dovecot.fi>
  Date:   2017-03-03 (Fri, 03 Mar 2017)

  Changed paths:
    M src/lib-oauth2/oauth2-introspect.c

  Log Message:
  -----------
  lib-oauth2: Add missing content-type header