When a subscription is created using cloudformation:
```
"ProfileChangedSubscription": {
      "Type": "AWS::SNS::Subscription",
      "Properties": {
        "Endpoint": {
          "Fn::GetAtt": [
            "ProfileChangedQueue",
            "Arn"
          ]
        },
        "Protocol": "sqs",
        "FilterPolicy": {
          "eventType": [
            "created"
          ]
        },
        "TopicArn": {
          "Fn::ImportValue": {
            "Fn::Sub": "${ProfilesProfilePublishStack}-ProfileChangedTopic"
          }
        }
      }
    }
```

The specified subscription filter policy is not created. When I run `get-subscription-attributes`, I get information about non-existing filter policy:

```
{
    "Attributes": {
        "TopicArn": "arn:aws:sns:us-east-1:000000000000:profile-changed-topic",
        "Endpoint": "arn:aws:sqs:us-east-1:000000000000:profile-changed-queue",
        "Protocol": "sqs",
        "SubscriptionArn": "arn:aws:sns:us-east-1:000000000000:profile-changed-topic:936a58be-525b-4228-bfdb-c4b2f6048e8c",
        "FilterPolicy": "None"
    }
}
```
s3 = aws_stack.connect_to_service('s3')
        cloudformation = aws_stack.connect_to_service('cloudformation')
        
        s3.create_bucket(Bucket=TEST_ARTIFACTS_BUCKET, ACL='public-read')
        s3.put_object(Bucket=TEST_ARTIFACTS_BUCKET, Key=TEST_ARTIFACTS_PATH, Body=TEST_TEMPLATE_5)
        
        buckets_before = len(s3.list_buckets()['Buckets'])
        stack_name = 'stack-%s' % short_uid()
        cloudformation.create_stack(StackName=stack_name, TemplateBody=TEST_TEMPLATE_6)
        
        buckets_after = len(s3.list_buckets()['Buckets'])
        self.assertEqual(buckets_after, buckets_before + 1)