Financial-Times/aggregate-concept-transformer: concept/service.go; 10 LoC

Found a possible issue in [Financial-Times/aggregate-concept-transformer](https://www.github.com/Financial-Times/aggregate-concept-transformer) at [concept/service.go](https://github.com/Financial-Times/aggregate-concept-transformer/blob/21d2ca0d61442cf6181e1c45a46b2a7de0252d2a/concept/service.go#L163-L172)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first
issue it finds, so please do not limit your consideration to the contents of the below message.

> range-loop variable n used in defer or goroutine at line 168

[Click here to see the code in its original context.](https://github.com/Financial-Times/aggregate-concept-transformer/blob/21d2ca0d61442cf6181e1c45a46b2a7de0252d2a/concept/service.go#L163-L172)

Click here to show the 10 line(s) of Go which triggered the analyzer.

```go
for _, n := range notifications {
go func(ctx context.Context, reqWG *sync.WaitGroup, update sqs.ConceptUpdate) {
defer reqWG.Done()
err := s.processConceptUpdate(ctx, update)
if err != nil {
logger.WithError(err).WithUUID(n.UUID).Error("Error processing message.")
}

}(listenCtx, &wg, n)
}

```

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See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: 21d2ca0d61442cf6181e1c45a46b2a7de0252d2a