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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))
  }
})
```

'MemorySize': func_details.memory_size,
        'LastModified': func_details.last_modified,
        'TracingConfig': {'Mode': 'PassThrough'},
        'RevisionId': func_version.get('RevisionId'),
        'State': 'Active',
        'LastUpdateStatus': 'Successful'
    }
    if func_details.dead_letter_config:
        result['DeadLetterConfig'] = func_details.dead_letter_config
    if func_details.envvars:
        result['Environment'] = {
            'Variables': func_details.envvars
        }
    if (always_add_version or version != '$LATEST') and len(result['FunctionArn'].split(':')) <= 7:
        result['FunctionArn'] += ':%s' % version
    return result
def forward_to_fallback_url(func_arn, data):
    """ If LAMBDA_FALLBACK_URL is configured, forward the invocation of this non-existing
        Lambda to the configured URL. """
    if not config.LAMBDA_FALLBACK_URL:
        return None
    lambda_name = aws_stack.lambda_function_name(func_arn)
    if config.LAMBDA_FALLBACK_URL.startswith('dynamodb://'):
        table_name = urlparse(config.LAMBDA_FALLBACK_URL.replace('dynamodb://', 'http://')).netloc
        dynamodb = aws_stack.connect_to_service('dynamodb')
        item = {
            'id': {'S': short_uid()},
            'timestamp': {'N': str(now_utc())},
            'payload': {'S': str(data)},
            'function_name': {'S': lambda_name}