docs: fix reference to datadog.ContextServerVariables
@@ -101,7 +101,7 @@ When talking to a different server, like the `eu` instance, change the `ContextS
```go
ctx = context.WithValue(ctx,
- common.ContextServerVariables,
+ datadog.ContextServerVariables,
map[string]string{
"site": "datadoghq.eu",
})
