Hide retired devices attached to worker.
Too many retired devices on one worker makes check confuse.
After this patch, user still can still change health from retired to good from page: https://validation.linaro.org/scheduler/alldevices or admin.
Too many retired devices on one worker makes check confuse.
After this patch, user still can still change health from retired to good from page: https://validation.linaro.org/scheduler/alldevices or admin.