Deployment fails due to todoList declaration in Serverless.yaml

[dhiman-halder]

An error occurred: todoListModel - Invalid model specified: Validation Result: warnings : [], errors : [Invalid model schema specified, Model reference must be in canonical form] (Service: AmazonApiGateway; Status Code: 400; Error Code: BadRequestException; Request ID: 6c275dd6-3a04-11e9-bf84-c90efc2270bf)