Fix ineffective break statement in dynamic output

I noticed this by running [staticcheck](https://staticcheck.dev).
Unfortunately, golangci-lint is still using a deprecated version
of this linter. See [here](golangci/golangci-lint#853)
and [here](golangci/golangci-lint#357).

Signed-off-by: Mihai Todor <todormihai@gmail.com>

internal/impl/io/output_dynamic_fan_out.go

@@ -257,6 +257,7 @@ func (d *dynamicFanOutOutputBroker) loop() {
 		_ = atomic.AddInt64(&ackPending, 1)
 		pendingResponses := int64(len(d.outputs))
 
+	outputsLoop:
 		for _, output := range d.outputs {
 			select {
 			case output.tsChan <- message.NewTransactionFunc(ts.Payload.ShallowCopy(), func(ctx context.Context, err error) error {
@@ -273,7 +274,7 @@ func (d *dynamicFanOutOutputBroker) loop() {
 				return nil
 			}):
 			case <-d.shutSig.CloseAtLeisureChan():
-				break // This signal will be caught again in the next loop
+				break outputsLoop // This signal will be caught again in the next loop
 			}
 		}
 		d.outputsMut.RUnlock()