fix(workerpool.go): move taskQueueChan initialization in Run method, …

…if AddTask is called before Run, will cause a panic.

common/utils/workerpool/workerpool.go

@@ -15,14 +15,13 @@ type WorkerPool struct {
 func NewWorkerPool(maxWorker int) *WorkerPool {
 	return &WorkerPool{
 		maxWorker:     maxWorker,
-		taskQueueChan: nil,
+		taskQueueChan: make(chan func()),
 		wg:            sync.WaitGroup{},
 	}
 }
 
 // Run runs WorkerPool
 func (vwp *WorkerPool) Run() {
-	vwp.taskQueueChan = make(chan func())
 	for i := 0; i < vwp.maxWorker; i++ {
 		go func() {
 			for task := range vwp.taskQueueChan {