[webkit-dev] Build bot workers aperez-{wpe, gtk}-ews to be offline for a week

Hello, I will be moving to a new office in the next week or two, and I need to shut these down today. In all goes as expected, it should be possible to bring them online in about a week. There are other workers for the GTK and EWS ports, so the queues will continue running normally--if a tad slower. In the meantime, my apologies for the inconvenience. Cheers, -Adrian