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# Type of request: This is a ...

[x ] bug report
[ ] feature request

# Detailed description

Not able to use the edge service to write metric data to cloudwatch via the javascript aws-sdk.

However, It **DOES** work when using the deprecated cloudwatch port.

## Expected behavior

Metric data to be visible when calling `awslocal cloudwatch list-metrics`

## Actual behavior

404 from edge service. No metric data is persisted, localstack instance logs the following info:

```
INFO:localstack.services.edge: Unable to determine forwarding port for API "monitoring" - please make sure this API is enabled via the SERVICES configuration
```

# Steps to reproduce

Run JS code in "Client code" section.
See 404 Error

## Command used to start LocalStack

`TMPDIR=/tmp/localstack docker-compose up`

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

```js
const AWS = require('aws-sdk')
const cw = new AWS.CloudWatch({
  endpoint: 'http://localhost:4566',
})

const data = {
  Namespace: 'ns',
  MetricData: [
    {
      MetricName: 'metric-name',
      Timestamp: new Date(),
      Value: 12345,
      Unit: 'Milliseconds',
      Dimensions: [
        { Name: 'Environment', Value: 'local' },
      ]
    }
  ]
}

cw.putMetricData(data, (err, data) => {
  if (err) {
      console.log('Error', err)
  } else {
      console.log('Success', JSON.stringify(data))
  }
})
```

'attributes': msg.get('Attributes', {}),
                'messageAttributes': message_attrs,
                'md5OfMessageAttributes': msg.get('MD5OfMessageAttributes'),
                'sqs': True,
            })
        event = {'Records': records}
        
        run_lambda(event=event, context={}, func_arn=lambda_arn, asynchronous=True, callback=delete_messages)
    def listener_loop(*args):
        while True:
            try:
                sources = get_event_sources(source_arn=r'.*:sqs:.*')
                if not sources:
                    
                    
                    
                    SQS_LISTENER_THREAD.pop('_thread_')
                    return
                sqs_client = aws_stack.connect_to_service('sqs')
                for source in sources:
                    queue_arn = source['EventSourceArn']
                    lambda_arn = source['FunctionArn']
                    batch_size = max(min(source.get('BatchSize', 1), 10), 1)
                    try:
                        region_name = queue_arn.split(':')[3]
                        queue_url = aws_stack.sqs_queue_url_for_arn(queue_arn)
                        result = sqs_client.receive_message(
                            QueueUrl=queue_url,
                            MessageAttributeNames=['All'],
                            MaxNumberOfMessages=batch_size