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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))
  }
})
```

}
    iam_client.create_policy(PolicyName=POLICY_NAME_PATTERN % function,
        PolicyDocument=json.dumps(policy), Description='Policy for Lambda function "%s"' % function)
    result = {'Statement': sid}
    return jsonify(result)
@app.route('%s/functions/<function>/policy/<statement>' % PATH_ROOT, methods=['DELETE'])
def remove_permission(function, statement):
    qualifier = request.args.get('Qualifier')
    iam_client = aws_stack.connect_to_service('iam')
    policy = get_lambda_policy(function)
    if not policy:
        return error_response('Unable to find policy for Lambda function "%s"' % function,
            404, error_type='ResourceNotFoundException')
    iam_client.delete_policy(PolicyArn=policy['PolicyArn'])
    result = {
        'FunctionName': function,
        'Qualifier': qualifier,
        'StatementId': policy['Statement'][0]['Sid'],
    }
    return jsonify(result)
@app.route('%s/functions/<function>/policy' % PATH_ROOT, methods=['GET'])
def get_policy(function):
    policy = get_lambda_policy(function)
    if not policy:
        return error_response('The resource you requested does not exist.',
            404, error_type='ResourceNotFoundException')
    return jsonify({'Policy': json.dumps(policy), 'RevisionId': 'test1234'})
@app.route('%s/functions/<function>/invocations' % PATH_ROOT, methods=['POST'])
def invoke_function(function):
    """ Invoke an existing function