Errant [ character makes a required argument look optional

https://api.dart.dev/stable/2.6.1/dart-core/Uri/Uri.https.html

```
Uri.https(
    String authority, [
    String unencodedPath, [
    Map<String, String> queryParameters
])
```

The `[` before `String unencodedPath` made me think it was part of the optional positional arguments, but it is a required argument.