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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))
  }
})
```

self._stdout = self.LogStreamIO()
        self._stderr = self.LogStreamIO()
    def __enter__(self):
        
        from werkzeug.local import LocalProxy
        ident = self._ident()
        if ident not in self.CONTEXTS_BY_THREAD:
            self.CONTEXTS_BY_THREAD[ident] = self
            self._set(LocalProxy(self._proxy(sys.stdout, 'stdout')),
                      LocalProxy(self._proxy(sys.stderr, 'stderr')),
                      LocalProxy(self._proxy(sys.__stdout__, 'stdout')),
                      LocalProxy(self._proxy(sys.__stderr__, 'stderr')))
        return self
    def __exit__(self, type, value, traceback):
        ident = self._ident()
        removed = self.CONTEXTS_BY_THREAD.pop(ident, None)
        if not self.CONTEXTS_BY_THREAD:
            
            self._set(self.orig_stdout, self.orig_stderr, self.orig___stdout, self.orig___stderr)
        
        removed._stdout.flush()
        removed._stderr.flush()
        out = removed._stdout.getvalue()
        err = removed._stderr.getvalue()
        
        removed._stdout.close()
        removed._stderr.close()
        removed._stdout = out
        removed._stderr = err
    def _set(self, out, err, __out, __err):