lmtp proxy: Don't internally finish proxying before client has even sent DATA command. This fixes some crashes when all recipients were invalid.
lmtp proxy: Don't internally finish proxying before client has even sent DATA command.
This fixes some crashes when all recipients were invalid.

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