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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))
  }
})
```

import os
import json
import time
import unittest
from botocore.exceptions import ClientError
from localstack.utils import testutil
from localstack.utils.testutil import get_lambda_log_events, get_lambda_log_group_name
from localstack.utils.aws import aws_stack
from localstack.utils.common import short_uid, retry
from .lambdas import lambda_integration
from .test_lambda import TEST_LAMBDA_PYTHON, LAMBDA_RUNTIME_PYTHON36, TEST_LAMBDA_LIBS
TEST_QUEUE_NAME = 'TestQueue'
TEST_POLICY = """
{
  "Version":"2012-10-17",
  "Statement":[
    {
      "Effect": "Allow",
      "Principal": { "AWS": "*" },
      "Action": "sqs:SendMessage",
      "Resource": "'$sqs_queue_arn'",
      "Condition":{
        "ArnEquals":{
        "aws:SourceArn":"'$sns_topic_arn'"
        }
      }
    }