fix(toolbox): Defensively check classNames when mapping button attributes
fix(toolbox): Defensively check classNames when mapping button attributes

bgrozev/jitsi-meet,bgrozev/jitsi-meet,gpolitis/jitsi-meet,bgrozev/jitsi-meet,jitsi/jitsi-meet,jitsi/jitsi-meet,jitsi/jitsi-meet,bgrozev/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,jitsi/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,bgrozev/jitsi-meet,gpolitis/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,gpolitis/jitsi-meet,bgrozev/jitsi-meet