func (e *ResolverGroup) SetEndpoints(endpoints []string) {
	addrs := epsToAddrs(endpoints...)
	e.mu.Lock()
	e.endpoints = endpoints
	for _, r := range e.resolvers {
		r.cc.NewAddress(addrs)
	}
	e.mu.Unlock()
}
func (e *ResolverGroup) SetEndpoints(endpoints []string) {
	addrs := epsToAddrs(endpoints...)
	e.mu.Lock()
	e.endpoints = endpoints
	for _, r := range e.resolvers {
		r.cc.NewAddress(addrs)
	}
	e.mu.Unlock()
}
// SetEndpoints updates the endpoints for ResolverGroup. All registered resolver are updated
// immediately with the new endpoints.