mdbox: Allow reflink-copying a mail when wanted GUID matches the current GUID.
mdbox: Allow reflink-copying a mail when wanted GUID matches the current GUID.

jkerihuel/dovecot,jkerihuel/dovecot,jkerihuel/dovecot,jkerihuel/dovecot,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jkerihuel/dovecot,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch