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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))
  }
})
```

try:
        func_arn = aws_stack.fix_arn(func_arn)
        func_details = arn_to_lambda.get(func_arn)
        if not func_details:
            return not_found_error(msg='The resource specified in the request does not exist.')
        if not context:
            context = LambdaContext(func_details, version)
        result = LAMBDA_EXECUTOR.execute(func_arn, func_details, event, context=context,
            version=version, asynchronous=asynchronous, callback=callback)
    except Exception as e:
        return error_response('Error executing Lambda function %s: %s %s' % (func_arn, e, traceback.format_exc()))
    finally:
        if suppress_output:
            sys.stdout = stdout_
            sys.stderr = stderr_
    return result
def exec_lambda_code(script, handler_function='handler', lambda_cwd=None, lambda_env=None):
    if lambda_cwd or lambda_env:
        EXEC_MUTEX.acquire()
        if lambda_cwd:
            previous_cwd = os.getcwd()
            os.chdir(lambda_cwd)
            sys.path = [lambda_cwd] + sys.path
        if lambda_env:
            previous_env = dict(os.environ)
            os.environ.update(lambda_env)
    
    lambda_id = 'l_%s' % short_uid()
    lambda_file = LAMBDA_SCRIPT_PATTERN.replace('*', lambda_id)
    save_file(lambda_file, script)