Application Insights - `WebTestLocations_List` returns a plain json array as response, instead of wrapped in a json

Originally reported: https://github.com/Azure/azure-sdk-for-go/issues/9284

The swagger defined the response of `WebTestLocations_List` [here](https://github.com/Azure/azure-rest-api-specs/blob/c18974133add20f6fea02092f5c3c85f954c52f5/specification/applicationinsights/resource-manager/Microsoft.Insights/stable/2015-05-01/webTestLocations_API.json#L80), which is expecting the response should be returned as a JSON like this:
```
{
"value": [
// the elements of the list result
]
}
```
instead, the response is just returning an array, like this:
```
[
// the elements of the list result
]
```

This issue is currently blocking go SDK from working properly.

Start with the linked webTestLocations_API.json definition for WebTestLocations_List and compare its declared response with the service behavior described in the issue. Confirm that the response is represented as an object containing a value array rather than a plain array; done means the specification matches the expected wrapped JSON shape.

Written by the indexing model from the issue text.