[Panic] init trace client, the same intstance

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**BUG REPORT**
3. Other information (e.g. detailed explanation, logs, related issues, suggestions on how to fix, etc):
panic log：

problem code:
trace.NewTraceDispatcher()
InstanceName is same,so clientID is same，traceConfig can not set InstanceName or UnitName

dispatcher not nil，but traceCli is nil，

the Start() method，td.running = true panic

**FEATURE REQUEST**

1. Please describe the feature you are requesting.
ClientID() method change to below, id add GroupName