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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))
  }
})
```

body_key = 'MD5OfMessageBody' if outgoing else 'MD5OfBody'
            return set([
                (m[body_key], m['MD5OfMessageAttributes'])
                for m in messages
            ])
        messages_to_send = [
            {
                'Id': 'message{:02d}'.format(i),
                'MessageBody': 'msgBody{:02d}'.format(i),
                'MessageAttributes': {
                    'CustomAttribute': {
                        'DataType': 'String',
                        'StringValue': 'CustomAttributeValue{:02d}'.format(i)
                    }
                }
            }
            for i in range(1, 11)
        ]
        resp = self.client.send_message_batch(QueueUrl=queue_url, Entries=messages_to_send)
        sent_hashes = get_hashes(resp.get('Successful', []), outgoing=True)
        self.assertEqual(len(sent_hashes), len(messages_to_send))
        for i in range(2):
            messages = receive_messages(VisibilityTimeout=0)['Messages']
            received_hashes = get_hashes(messages)
            self.assertEqual(received_hashes, sent_hashes)
        self.client.delete_message_batch(
            QueueUrl=queue_url,
            Entries=[