diamondburned/ningen: md/mention.go; 7 LoC

Found a possible issue in [diamondburned/ningen](https://www.github.com/diamondburned/ningen) at [md/mention.go](https://github.com/diamondburned/ningen/blob/ce64ffb0bb120b2e535a7ab4c7d394be5fb9cbf7/md/mention.go#L95-L101)

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.

> reference to user is reassigned at line 97

[Click here to see the code in its original context.](https://github.com/diamondburned/ningen/blob/ce64ffb0bb120b2e535a7ab4c7d394be5fb9cbf7/md/mention.go#L95-L101)

Click here to show the 7 line(s) of Go which triggered the analyzer.

```go
for _, user := range msg.Mentions {
if user.ID == d {
target = &user
mentioned = true // user is mentioned
break
}
}

```

Leave a reaction on this issue to contribute to the project by classifying this instance as a **Bug** :-1:, **Mitigated** :+1:, or **Desirable Behavior** :rocket:
See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: ce64ffb0bb120b2e535a7ab4c7d394be5fb9cbf7

Review md/mention.go at lines 95-101 in diamondburned/ningen and compare the analyzer report with the surrounding range-loop code. Done means determining whether the finding is a Bug, Mitigated, or Desirable Behavior and leaving the corresponding reaction.

Written by the indexing model from the issue text.