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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:
        credential_scope = auth_header.split(',')[0].split()[1]
        _, _, _, service, _ = credential_scope.split('/')
        result = service, get_service_port_for_account(service, headers)
    except Exception:
        pass
    result_before = result
    
    if host.endswith('cloudfront.net'):
        path = path or '/'
        result = 'cloudfront', config.PORT_CLOUDFRONT
    elif target.startswith('AWSCognitoIdentityProviderService') or 'cognito-idp.' in host:
        result = 'cognito-idp', config.PORT_COGNITO_IDP
    elif target.startswith('AWSCognitoIdentityService') or 'cognito-identity.' in host:
        result = 'cognito-identity', config.PORT_COGNITO_IDENTITY
    elif result[0] == 's3' or re.match(r'.*s3(\-website)?\.([^\.]+\.)?amazonaws.com', host):
        host = re.sub(r's3-website\..*\.amazonaws', 's3.amazonaws', host)
        result = 's3', config.PORT_S3
    elif result[0] == 'states' in auth_header or host.startswith('states.'):
        result = 'stepfunctions', config.PORT_STEPFUNCTIONS
    elif '.execute-api.' in host:
        result = 'apigateway', config.PORT_APIGATEWAY
    elif target.startswith('DynamoDBStreams') or host.startswith('streams.dynamodb.'):
        
        result = result_before = 'dynamodbstreams', config.PORT_DYNAMODBSTREAMS
    elif ls_target == 'web' or path == '/graph':
        result = 'web', config.PORT_WEB_UI
    return result[0], result_before[1] or result[1], path, host
def is_s3_form_data(data_bytes):