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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))
  }
})
```

raise_error = None
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        time.sleep(sleep_before)
    for i in range(0, retries + 1):
        try:
            return function(**kwargs)
        except Exception as error:
            raise_error = error
            time.sleep(sleep)
    raise raise_error
def dump_thread_info():
    for t in threading.enumerate():
        print(t)
    print(run("ps aux | grep 'node\\|java\\|python'"))
def merge_recursive(source, destination, none_values=[None]):
    for key, value in source.items():
        if isinstance(value, dict):
            
            node = destination.setdefault(key, {})
            merge_recursive(value, node)
        else:
            if not isinstance(destination, dict):
                LOG.warning('Destination for merging %s=%s is not dict: %s' %
                    (key, value, destination))
            if destination.get(key) in none_values:
                destination[key] = value
    return destination
def merge_dicts(*dicts, **kwargs):