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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.

response = Response()
    response._content = """<ErrorResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/"><Error>
        <Type>Sender</Type>
        <Code>{code_string}</Code>
        <Message>{message}</Message>
        </Error><RequestId>{req_id}</RequestId>
        </ErrorResponse>""".format(message=message, code_string=code_string, req_id=short_uid())
    response.status_code = code
    return response
def create_sns_message_body(subscriber, req_data, message_id=None):
    message = req_data['Message'][0]
    protocol = subscriber['Protocol']
    if six.PY2 and type(message).__name__ == 'unicode':
        
        message = message.encode('raw-unicode-escape')
    if is_raw_message_delivery(subscriber):
        return message
    if req_data.get('MessageStructure') == ['json']:
        message = json.loads(message)
        try:
            message = message.get(protocol, message['default'])
        except KeyError:
            raise Exception("Unable to find 'default' key in message payload")
    data = {
        'Type': req_data.get('Type', ['Notification'])[0],
        'MessageId': message_id,
        'TopicArn': subscriber['TopicArn'],