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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))
  }
})
```

func_region = f_arn.split(':')[3]
        if func_region != this_region:
            continue
        func_name = f_arn.split(':function:')[-1]
        arn = func_arn(func_name)
        func_details = arn_to_lambda.get(arn)
        if not func_details:
            
            continue
        details = format_func_details(func_details)
        details['Tags'] = func.tags
        funcs.append(details)
    return funcs
def format_func_details(func_details, version=None, always_add_version=False):
    version = version or '$LATEST'
    func_version = func_details.get_version(version)
    result = {
        'CodeSha256': func_version.get('CodeSha256'),
        'Role': func_details.role,
        'KMSKeyArn': func_details.kms_key_arn,
        'Version': version,
        'VpcConfig': func_details.vpc_config,
        'FunctionArn': func_details.arn(),
        'FunctionName': func_details.name(),
        'CodeSize': func_version.get('CodeSize'),
        'Handler': func_details.handler,
        'Runtime': func_details.runtime,
        'Timeout': func_details.timeout,
        'Description': func_details.description,