Fix range variable bug found by vet
Fix range variable bug found by vet

We can't directly use a range var in a go func, since the actual value
in memory will be overwritten by further iterations. We need to lock the
value in by copying it, such as passing it as an argument to the func.

mvdan/tyk,mvdan/tyk,nebolsin/tyk,lonelycode/tyk,nebolsin/tyk,nebolsin/tyk,lonelycode/tyk,mvdan/tyk,lonelycode/tyk,nebolsin/tyk,mvdan/tyk,nebolsin/tyk,mvdan/tyk,nebolsin/tyk,mvdan/tyk,nebolsin/tyk,nebolsin/tyk,mvdan/tyk,mvdan/tyk