PrepareController middleware is being run too early (before user-defined middleware) since beta4?

Since we last upgraded Dingo API, we started having strange issues on our API. I'm pretty sure I narrowed down the issue to the switch between beta3 and beta4, ~~but I'm not 100% certain~~ confirmed as true.

We declare route middlewares like this:
```php
$app->routeMiddleware([
'mw1' => Middleware1::class,
'mw2' => Middleware2::class,
'mw3' => Middleware3::class,
]);
```

And we use them like this:
```php
$api = app(Router::class);
$api->version(
'v1',
function ($api) {
$api->group(
['middleware' => ['mw1', 'mw2', 'mw3']],
function ($api) {
$api->get(
'/endpoint/{parameter}',
Controllers\EndpointController::class
);
}
);
}
);
```

None of the middlewares are actually applied. The middlewares themselves don't seem to be related to the issue, they are not even instantiated once. I tried switching them to application middlewares with `$app->middleware()` instead and the problem disappears. It's just that I can't have these run for every request, so it's not a suitable workaround. Also, it doesn't seem to work either when I switch them to a single route.

Is that something we're doing wrong or did something change recently? Seems strange that we'd be the only ones to have this issue.