error init heartbeatTimer while connect

[viras777]

1. Connect to workerman
2. Connect to rabbitMQ
3. Init heartbeatTimer NOT ONCE
4. Exec func heartbeat and ADD once timer. Total 2 heartbeatTimer
5. Disconnect workerman and rabbitmq, del once heartbeatTimer
6. Ta-daa-m, exec heartbeatTimer from step 3 and get exception, and die workerman