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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))
  }
})
```

dynamodb = aws_stack.connect_to_service('dynamodb')
                table_name = table_name_from_stream_arn(stream['StreamArn'])
                stream_name = get_kinesis_stream_name(table_name)
                stream_details = kinesis.describe_stream(StreamName=stream_name)
                table_details = dynamodb.describe_table(TableName=table_name)
                stream['KeySchema'] = table_details['Table']['KeySchema']
                
                
                stream_shards = stream_details['StreamDescription']['Shards']
                for shard in stream_shards:
                    shard['ShardId'] = shard_id(stream_name, shard['ShardId'])
                stream['Shards'] = stream_shards
                break
        if not result:
            return error_response('Requested resource not found', error_type='ResourceNotFoundException')
    elif action == '%s.GetShardIterator' % ACTION_HEADER_PREFIX:
        
        stream_name = stream_name_from_stream_arn(data['StreamArn'])
        stream_shard_id = kinesis_shard_id(data['ShardId'])
        result = kinesis.get_shard_iterator(StreamName=stream_name,
            ShardId=stream_shard_id, ShardIteratorType=data['ShardIteratorType'])
    elif action == '%s.GetRecords' % ACTION_HEADER_PREFIX:
        kinesis_records = kinesis.get_records(**data)
        result = {'Records': [], 'NextShardIterator': kinesis_records.get('NextShardIterator')}
        for record in kinesis_records['Records']:
            result['Records'].append(json.loads(to_str(record['Data'])))
    else:
        print('WARNING: Unknown operation "%s"' % action)
    return jsonify(result)
def error_response(message=None, error_type=None, code=400):