It is my understanding that setting an environment varialbe `TEST_AWS_ACCOUNT_ID` for localstack sets that as the AWS account for the user in localstack.

However, setting it does not actually change any ARNs. For example:

1. Start localstack using `TEST_AWS_ACCOUNT_ID="111111111111" DEBUG=1 localstack start`
2. Deploy anything with an ARN (in this example I deployed a lambda)
3. Check the ARN. Example output for lambda:
```json
$ awslocal lambda list-functions
{
    "Functions": [
        {
            "FunctionName": "localtest-local-hello",
            "FunctionArn": "arn:aws:lambda:us-east-1:000000000000:function:localtest-local-hello",
            "Runtime": "nodejs10.x",
            "Role": "test_role",
            "Handler": "handler.hello",
            "CodeSize": 3077,
            "Description": "",
            "Timeout": 6,
            "MemorySize": 1024,
            "LastModified": "2019-11-06T06:43:53.451+0000",
            "CodeSha256": "V77gR13o90ET7+XquXBBc3Rxr1qDu1bE7S+A0Wbx5ys=",
            "Version": "$LATEST",
            "TracingConfig": {
                "Mode": "PassThrough"
            },
            "RevisionId": "3d4ed679-c1a9-4b7e-ad9e-f27e8543c5e9"
        }
    ]
}
```

ARN is still 000000000000
LOG.warning('Unable to update resource type "%s", id "%s"' % (resource_type, resource_id))
        return
    LOG.info('Updating resource %s of type %s' % (resource_id, resource_type))
    props = resource['Properties']
    if resource_type == 'Lambda::Function':
        client = aws_stack.connect_to_service('lambda')
        keys = ('FunctionName', 'Role', 'Handler', 'Description', 'Timeout', 'MemorySize', 'Environment', 'Runtime')
        update_props = dict([(k, props[k]) for k in keys if k in props])
        update_props = resolve_refs_recursively(stack_name, update_props, resources)
        if 'Code' in props:
            client.update_function_code(FunctionName=props['FunctionName'], **props['Code'])
        return client.update_function_configuration(**update_props)
    if resource_type == 'ApiGateway::Method':
        client = aws_stack.connect_to_service('apigateway')
        integration = props.get('Integration')
        
        kwargs = {
            'restApiId': props['RestApiId'],
            'resourceId': props['ResourceId'],
            'httpMethod': props['HttpMethod'],
            'requestParameters': props.get('RequestParameters')
        }
        if integration:
            kwargs['type'] = integration['Type']
            kwargs['integrationHttpMethod'] = integration.get('IntegrationHttpMethod')
            kwargs['uri'] = integration.get('Uri')
            return client.put_integration(**kwargs)
        kwargs['authorizationType'] = props.get('AuthorizationType')
        return client.put_method(**kwargs)
def convert_data_types(func_details, params):