CREATE_FAILED: ApiGatewayMethodActionPost (AWS::ApiGateway::Method) - Invalid type for parameter selectionPattern

I'm trying to deploy my serverless app on local stack but Invalid type parameter for selectionPattern error is being thrown. Below is the complete error and serverless.yml

Error:

ApiGatewayMethodActionPost (Parameter validation failed:; Invalid type for parameter selectionPattern, value: 200, type: <class 'int'>, valid types: <class 'str'>)

serverless.yml

  events:
    - http:
        path: /action
        method: POST
        iamRole: arn:aws:iam::xxxxxxxxxxxx:role/someRole
        action: StartSyncExecution
        request:
          template:
            application/json: |
              {
                "stateMachineArn":"arn:aws:states:'us-west-2':xxxxxxxxxxxx:stateMachine:someMachine",
                "input": "$util.escapeJavaScript($input.json('$'))"
              }
        response:
            template: 
              application/json: |
                $input.path('$.output')

I was checking serverless-step-function code where selectionPattern is defined as integer and not string. Following is the link to the code: code

Comienza con la configuración serverless.yml del informe y compárala con el código vinculado de serverless-step-functions lib/deploy/events/apiGateway/methods.js en la línea 199. Reproduce el despliegue contra LocalStack, rastrea cómo se genera selectionPattern y confirma la corrección verificando que el método de API Gateway se despliega sin el error de tipo de parámetro.