SAM Policy Template StepFunctionsExecutionPolicy generated role looks incorrect

template.yaml

This template.yaml file 
# snip

  - StepFunctionsExecutionPolicy: # Manually change to StartSyncExection after deployment
      StateMachineName:
        !Ref ProcessImageStateMachineExpressSync

# snip

generates this role

{
    "Statement": [
        {
            "Action": [
                "states:StartExecution"
            ],
            "Resource": "arn:aws:states:us-west-1:xxxxxxx:stateMachine:arn:aws:states:us-west-1:xxxxxxx:stateMachine:ProcessImageStateMachineExpressSync-w4tFUSVsowaT",
            "Effect": "Allow"
        }
    ]
}

Note the duplicate arn on line 18.