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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.

'TopicArn': topic_arn,
        'Endpoint': endpoint,
        'Protocol': protocol,
        'SubscriptionArn': subscription_arn,
        'FilterPolicy': filter_policy
    }
    subscription.update(attributes)
    topic_subs.append(subscription)
    if subscription_arn not in SUBSCRIPTION_STATUS:
        SUBSCRIPTION_STATUS[subscription_arn] = {}
    SUBSCRIPTION_STATUS[subscription_arn].update(
        {
            'TopicArn': topic_arn,
            'Token': short_uid(),
            'Status': 'Not Subscribed'
        }
    )
    
    if protocol in ['http', 'https']:
        token = short_uid()
        external_url = external_service_url('sns')
        confirmation = {
            'Type': ['SubscriptionConfirmation'],
            'Token': [token],
            'Message': [('You have chosen to subscribe to the topic %s.\n' % topic_arn) +
                        'To confirm the subscription, visit the SubscribeURL included in this message.'],
            'SubscribeURL': ['%s/?Action=ConfirmSubscription&TopicArn=%s&Token=%s' % (external_url, topic_arn, token)]
        }
        publish_message(topic_arn, confirmation, subscription_arn, skip_checks=True)
def do_unsubscribe(subscription_arn):