Don't crash if keyword update doesn't actually have any keywords set.
Don't crash if keyword update doesn't actually have any keywords set.

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,damoxc/dovecot,LTD-Beget/dovecot,damoxc/dovecot,damoxc/dovecot,Distrotech/dovecot,LTD-Beget/dovecot,damoxc/dovecot,Distrotech/dovecot,damoxc/dovecot,Distrotech/dovecot,Distrotech/dovecot,Distrotech/dovecot