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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))
  }
})
```

lambda_name, 409, error_type='ResourceConflictException')
        arn_to_lambda[arn] = func_details = LambdaFunction(arn)
        func_details.versions = {'$LATEST': {'RevisionId': str(uuid.uuid4())}}
        func_details.vpc_config = data.get('VpcConfig', {})
        func_details.last_modified = isoformat_milliseconds(datetime.utcnow()) + '+0000'
        func_details.description = data.get('Description', '')
        func_details.handler = data['Handler']
        func_details.runtime = data['Runtime']
        func_details.envvars = data.get('Environment', {}).get('Variables', {})
        func_details.tags = data.get('Tags', {})
        func_details.timeout = data.get('Timeout', LAMBDA_DEFAULT_TIMEOUT)
        func_details.role = data['Role']
        func_details.kms_key_arn = data.get('KMSKeyArn')
        func_details.memory_size = data.get('MemorySize')
        func_details.code = data['Code']
        func_details.set_dead_letter_config(data)
        result = set_function_code(func_details.code, lambda_name)
        if isinstance(result, Response):
            del arn_to_lambda[arn]
            return result
        
        func_details.code.pop('ZipFile', None)
        
        result.update(format_func_details(func_details))
        if data.get('Publish', False):
            result['Version'] = publish_new_function_version(arn)['Version']
        return jsonify(result or {})
    except Exception as e:
        arn_to_lambda.pop(arn, None)
        if isinstance(e, ClientError):