application-load-balanced-fargate-service: No Fargate configuration exists for given values: 512 CPU , 512 memory

[FredericHeem]

Hi, While trying to deploy the application-load-balanced-fargate-service examples, CDK fails with the following error:

13:47:44 | CREATE_FAILED        | AWS::ECS::TaskDefinition                  | amazon-ecs-sample/TaskDef
Resource handler returned message: "Invalid request provided: Create TaskDefinition: No Fargate configuration exists for given values: 512 CPU
, 512 memory. See the Amazon ECS documentation for the valid values. (Service: AmazonECS; Status Code: 400; Error Code: ClientException; Reque

[vhartikainen]

Created a #2 to fix this issue of memoryLimitMiB defaulting to 512. This is not a supported task configuration in Fargate (at least anymore).

[dannysteenman]

Thanks for the PR ;)