SevereCloud/vksdk: events/events.go; 7 LoC

Found a possible issue in [SevereCloud/vksdk](https://www.github.com/SevereCloud/vksdk) at [events/events.go](https://github.com/SevereCloud/vksdk/blob/691e87e001d589843dc43441a2d4b2a82e8972ce/events/events.go#L816-L822)

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 f used in defer or goroutine at line 818

[Click here to see the code in its original context.](https://github.com/SevereCloud/vksdk/blob/691e87e001d589843dc43441a2d4b2a82e8972ce/events/events.go#L816-L822)

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

```go
for _, f := range fl.donutSubscriptionProlonged {
if fl.goroutine {
go func() { f(ctx, obj) }()
} else {
f(ctx, obj)
}
}

```

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: 691e87e001d589843dc43441a2d4b2a82e8972ce

Start by reading events/events.go around lines 816-822, focusing on the range loop and its goroutine branch. Confirm the analyzer warning against the callback behavior shown there, then verify that the warning is addressed without changing the synchronous path; the issue provides no test file, so use the repository's existing checks.

Written by the indexing model from the issue text.