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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))
  }
})
```

for i, m in enumerate(event_source_mappings):
        if uuid_value == m['UUID']:
            return event_source_mappings.pop(i)
    return {}
def use_docker():
    global DO_USE_DOCKER
    if DO_USE_DOCKER is None:
        DO_USE_DOCKER = False
        if 'docker' in config.LAMBDA_EXECUTOR:
            try:
                run('docker images', print_error=False)
                DO_USE_DOCKER = True
            except Exception:
                pass
    return DO_USE_DOCKER
def get_stage_variables(api_id, stage):
    api_gateway_client = aws_stack.connect_to_service('apigateway')
    response = api_gateway_client.get_stage(restApiId=api_id, stageName=stage)
    return response.get('variables', None)
def fix_proxy_path_params(path_params):
    proxy_path_param_value = path_params.get('proxy+')
    if not proxy_path_param_value:
        return
    del path_params['proxy+']
    path_params['proxy'] = proxy_path_param_value
def message_attributes_to_lower(message_attrs):