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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

SNS is unable to forward the message to SQS (non fifo queue) when using the `elasticmq` backend and fails with the following log
```
2021-01-19T09:31:50:WARNING:localstack.services.sns.sns_listener: Unable to forward SNS message to SQS: An error occurred (InvalidParameterValue) when calling the SendMessage operation: Value for parameter MessageGroupId is invalid. The request include parameter that is not valid for this queue type Traceback (most recent call last):

File "/opt/code/localstack/localstack/services/sns/sns_listener.py", line 297, in message_to_subscribers

sqs_client.send_message(

File "/opt/code/localstack/.venv/lib/python3.8/site-packages/botocore/client.py", line 357, in _api_call

return self._make_api_call(operation_name, kwargs)

File "/opt/code/localstack/.venv/lib/python3.8/site-packages/botocore/client.py", line 676, in _make_api_call

raise error_class(parsed_response, operation_name)

botocore.exceptions.ClientError: An error occurred (InvalidParameterValue) when calling the SendMessage operation: Value for parameter MessageGroupId is invalid. The request include parameter that is not valid for this queue type
```
This is likely a regression due to #3435. Tested with the default backend on `0.12.5` and it works as expected. Also works with `elasticmq` backend on `0.12.4`

## Expected behavior

Same behavior with the `elasticmq` backend as with the default backend.

## Actual behavior

Fails on `elasticmq` backend, no SQS message received when SNS message is sent.

# Steps to reproduce

## Command used to start LocalStack

```yaml
  localstack:
    image: localstack/localstack:0.12.5
    ports:
      - 4566:4566
    environment:
      - AWS_DEFAULT_REGION=ap-northeast-1
      - SERVICES=sns,sqs
      - SQS_PROVIDER=elasticmq
```

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
N.A.

self._extract_tags(topic_arn, req_data, False)
                return make_response(req_action)
            elif req_action == 'UntagResource':
                tags_to_remove = []
                req_tags = {k: v for k, v in req_data.items() if k.startswith('TagKeys.member.')}
                req_tags = req_tags.values()
                for tag in req_tags:
                    tags_to_remove.append(tag[0])
                do_untag_resource(topic_arn, tags_to_remove)
                return make_response(req_action)
            data = self._reset_account_id(data)
            return Request(data=data, headers=headers, method=method)
        return True
    @staticmethod
    def _extract_tags(topic_arn, req_data, is_create_topic_request):
        tags = []
        req_tags = {k: v for k, v in req_data.items() if k.startswith('Tags.member.')}
        for i in range(int(len(req_tags.keys()) / 2)):
            key = req_tags['Tags.member.' + str(i + 1) + '.Key'][0]
            value = req_tags['Tags.member.' + str(i + 1) + '.Value'][0]
            tags.append({'Key': key, 'Value': value})
            
            
            existing_tags = SNS_TAGS.get(topic_arn, None)
            if is_create_topic_request and existing_tags is not None and existing_tags != tags:
                return False
        do_tag_resource(topic_arn, tags)
        return True
    @staticmethod
    def _reset_account_id(data):