If namespace has a prefix and inbox=no, don't list prefix.inbox if it happens to exist when listing for %.
If namespace has a prefix and inbox=no, don't list prefix.inbox if it
happens to exist when listing for %.

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot