UNRESOLVABLE_REFERENCE when adding security definitions for AAD Token auth in Swagger 2.0

I’m looking at the [AutoRest authentication documentation on GitHub](https://github.com/Azure/autorest/blob/main/docs/generate/authentication.md), where it says that I can declare that my REST API uses AAD Token authentication in Swagger 2.0 like this:

```json
{
"securityDefinitions": {
"AADToken": {
"type": "oauth2",
"flow": "accessCode",
"authorizationUrl": "https://login.microsoftonline.com/common/v2.0/oauth2/authorize",
"tokenUrl": "https://login.microsoftonline.com/common/v2.0/oauth2/token"
}
},
"security": [
{
"AADToken": ["https://myservice.azure.com/.default"]
}
]
}
```

I added this to my swagger spec and replaced `"https://myservice.azure.com/.default"` accordingly. When I create a PR to commit my swagger spec into the azure-rest-api-specs repo, CI validation fails during the semantic validation check with an UNRESOLVABLE_REFERENCE error and a message saying "Security scope definition could not be resolved" and pointing to the AADToken URL that I replaced above. I contacted the AutoRest team and they suggested that this appears to be an issue with OAV.