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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))
  }
})
```

return json.dumps(obj, sort_keys=True)
def save_file(file, content, append=False):
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        mode = mode + 'b'
    with open(file, mode) as f:
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        f.flush()
def load_file(file_path, default=None, mode=None):
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        return default
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    with open(file_path, mode) as f:
        result = f.read()
    return result
def to_str(obj, encoding=DEFAULT_ENCODING, errors='strict'):
    """ If ``obj`` is an instance of ``binary_type``, return
    ``obj.decode(encoding, errors)``, otherwise return ``obj`` """
    return obj.decode(encoding, errors) if isinstance(obj, six.binary_type) else obj
def to_bytes(obj, encoding=DEFAULT_ENCODING, errors='strict'):
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    return obj.encode(encoding, errors) if isinstance(obj, six.text_type) else obj
def cleanup(files=True, env=ENV_DEV, quiet=True):
    if files:
        cleanup_tmp_files()
def cleanup_threads_and_processes(quiet=True):