[Authorization] Invalid swagger - duplicate API path

Path "/{scope}/providers/Microsoft.Authorization/roleDefinitions/{roleDefinitionId}" GET looks to be duplicated:
- https://github.com/Azure/azure-rest-api-specs/blob/master/arm-authorization/2015-07-01/swagger/authorization.json#L653
- https://github.com/Azure/azure-rest-api-specs/blob/master/arm-authorization/2015-07-01/swagger/authorization.json#L769  

[Error: The Swagger document(s) are invalid]
       errors: 
        [ { code: 'DUPLICATE_API_PATH',
            message: 'API path (or equivalent) already defined: /{roleDefinitionId}',
            path: [ 'paths', '/{roleDefinitionId}' ] } ],
       failedValidation: true
      

Open arm-authorization/2015-07-01/swagger/authorization.json and compare the GET definitions near lines 653 and 769 for the duplicated /{scope}/providers/Microsoft.Authorization/roleDefinitions/{roleDefinitionId} path. Determine the intended single definition, then run the Swagger validation that reported DUPLICATE_API_PATH; done means the document validates without that duplicate-path error.

Written by the indexing model from the issue text.