failed when using in Beijing region or Ningxia region

Hi,

I try to use this in AWS China regions (BJS and ZHY) but failed, I checked error log, found the domain URL is not the right one.

It could pass build image, but failed when try to push image to ECR.

```
[Container] 2022/05/18 04:10:55 Running command docker push $AWS_ACCOUNT_ID.dkr.ecr.$AWS_DEFAULT_REGION.amazonaws.com/$IMAGE_REPO_NAME:$IMAGE_TAG
185 | The push refers to repository [MY_AWS_ACCOUNT_ID.dkr.ecr.cn-northwest-1.amazonaws.com/unipus-anti-fraud-pipelines-sagemaker-processing-container]
186 | Get "https://MY_AWS_ACCOUNT_ID.dkr.ecr.cn-northwest-1.amazonaws.com/v2/": dial tcp: lookup MY_AWS_ACCOUNT_ID.dkr.ecr.cn-northwest-1.amazonaws.com on 10.0.0.2:53: no such host
187 |  
188 | [Container] 2022/05/18 04:10:55 Command did not exit successfully docker push $AWS_ACCOUNT_ID.dkr.ecr.$AWS_DEFAULT_REGION.amazonaws.com/$IMAGE_REPO_NAME:$IMAGE_TAG exit status 1
189 | [Container] 2022/05/18 04:10:55 Phase complete: POST_BUILD State: FAILED
190 | [Container] 2022/05/18 04:10:55 Phase context status code: COMMAND_EXECUTION_ERROR Message: Error while executing command: docker push $AWS_ACCOUNT_ID.dkr.ecr.$AWS_DEFAULT_REGION.amazonaws.com/$IMAGE_REPO_NAME:$IMAGE_TAG. Reason: exit status 1
191


```

Acctually, for BJS or ZHY region, there will be an **'.cn'** in the end of the domain URL, for example "MY_AWS_ACCOUNT_ID.dkr.ecr.cn-northwest-1.amazonaws.com.cn", this is different than other AWS global regions.

Could you fix this issue, thanks a lot.