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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))
  }
})
```

aws_stack.create_dynamodb_table(
            TEST_DDB_TABLE_NAME_4,
            partition_key=PARTITION_KEY,
            stream_view_type='NEW_AND_OLD_IMAGES'
        )
        table = self.dynamodb.Table(TEST_DDB_TABLE_NAME_4)
        expected_arn_prefix = 'arn:aws:dynamodb:' + aws_stack.get_local_region()
        self.assertTrue(table.table_arn.startswith(expected_arn_prefix))
        self.assertTrue(table.latest_stream_arn.startswith(expected_arn_prefix))
        # cl
        delete_table(TEST_DDB_TABLE_NAME_4)
    def test_multiple_update_expressions(self):
        dynamodb = aws_stack.connect_to_service('dynamodb')
        aws_stack.create_dynamodb_table(TEST_DDB_TABLE_NAME, partition_key=PARTITION_KEY)
        table = self.dynamodb.Table(TEST_DDB_TABLE_NAME)
        item_id = short_uid()
        table.put_item(Item={PARTITION_KEY: item_id, 'data': 'foobar123 ✓'})
        response = dynamodb.update_item(TableName=TEST_DDB_TABLE_NAME,
            Key={PARTITION_KEY: {'S': item_id}},
            UpdateExpression='SET attr1 = :v1, attr2 = :v2',
            ExpressionAttributeValues={
                ':v1': {'S': 'value1'},
                ':v2': {'S': 'value2'}
            })
        self.assertEqual(response['ResponseMetadata']['HTTPStatusCode'], 200)
        item = table.get_item(Key={PARTITION_KEY: item_id})['Item']
        self.assertEqual(item['attr1'], 'value1')
        self.assertEqual(item['attr2'], 'value2')
    def test_return_values_in_put_item(self):