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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.tag_resource(
            ResourceArn=table_arn,
            Tags=[
                {
                    'Key': 'NewKey',
                    'Value': 'TestValue'
                }
            ]
        )
        rs = dynamodb.list_tags_of_resource(
            ResourceArn=table_arn
        )
        self.assertEqual(len(rs['Tags']), len(TEST_DDB_TAGS) + 1)
        tags = {tag['Key']: tag['Value'] for tag in rs['Tags']}
        self.assertIn('NewKey', tags.keys())
        self.assertEqual(tags['NewKey'], 'TestValue')
        dynamodb.untag_resource(
            ResourceArn=table_arn,
            TagKeys=[
                'Name', 'NewKey'
            ]
        )
        rs = dynamodb.list_tags_of_resource(
            ResourceArn=table_arn
        )
        tags = {tag['Key']: tag['Value'] for tag in rs['Tags']}
        self.assertNotIn('Name', tags.keys())
        self.assertNotIn('NewKey', tags.keys())
        delete_table(table_name)
    def test_region_replacement(self):