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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))
  }
})
```

return 1000 * 60
def cleanup():
    global event_source_mappings, arn_to_lambda
    arn_to_lambda = {}
    event_source_mappings = []
    LAMBDA_EXECUTOR.cleanup()
def func_arn(function_name):
    return aws_stack.lambda_function_arn(function_name)
def check_batch_size_range(source_arn, batch_size=None):
    batch_size_entry = BATCH_SIZE_RANGES.get(source_arn.split(':')[2].lower())
    if not batch_size_entry:
        raise ValueError(
            INVALID_PARAMETER_VALUE_EXCEPTION, 'Unsupported event source type'
        )
    batch_size = batch_size or batch_size_entry[0]
    if batch_size > batch_size_entry[1]:
        raise ValueError(
            INVALID_PARAMETER_VALUE_EXCEPTION,
            'BatchSize {} exceeds the max of {}'.format(batch_size, batch_size_entry[1])
        )
    return batch_size
def add_function_mapping(lambda_name, lambda_handler, lambda_cwd=None):
    arn = func_arn(lambda_name)
    arn_to_lambda[arn].versions.get('$LATEST')['Function'] = lambda_handler
    arn_to_lambda[arn].cwd = lambda_cwd
def add_event_source(function_name, source_arn, enabled, batch_size=None):