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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))
  }
})
```

LAMBDA_RUNTIMES = [LAMBDA_RUNTIME_PYTHON27, LAMBDA_RUNTIME_PYTHON36, LAMBDA_RUNTIME_PYTHON37,
    LAMBDA_RUNTIME_PYTHON38, LAMBDA_RUNTIME_DOTNETCORE2, LAMBDA_RUNTIME_DOTNETCORE21, LAMBDA_RUNTIME_DOTNETCORE31,
    LAMBDA_RUNTIME_NODEJS, LAMBDA_RUNTIME_NODEJS610, LAMBDA_RUNTIME_NODEJS810,
    LAMBDA_RUNTIME_JAVA8, LAMBDA_RUNTIME_JAVA11, LAMBDA_RUNTIME_RUBY, LAMBDA_RUNTIME_RUBY25]
DOTNET_LAMBDA_RUNTIMES = [LAMBDA_RUNTIME_DOTNETCORE2, LAMBDA_RUNTIME_DOTNETCORE21, LAMBDA_RUNTIME_DOTNETCORE31]
LAMBDA_DEFAULT_TIMEOUT = 3
LAMBDA_DEFAULT_HANDLER = 'handler.handler'
LAMBDA_DEFAULT_RUNTIME = LAMBDA_RUNTIME_PYTHON38
LAMBDA_DEFAULT_STARTING_POSITION = 'LATEST'
LAMBDA_ZIP_FILE_NAME = 'original_lambda_archive.zip'
LAMBDA_JAR_FILE_NAME = 'original_lambda_archive.jar'
INVALID_PARAMETER_VALUE_EXCEPTION = 'InvalidParameterValueException'
BATCH_SIZE_RANGES = {
    'kinesis': (100, 10000),
    'dynamodb': (100, 1000),
    'sqs': (10, 10)
}
app = Flask(APP_NAME)
arn_to_lambda = {}
event_source_mappings = []
LOG = logging.getLogger(__name__)
EXEC_MUTEX = threading.Semaphore(1)
DO_USE_DOCKER = None
JSON_START_CHAR_MAP = {
    list: ('[',),
    tuple: ('[',),
    dict: ('{',),
    str: ('"',),
    bytes: ('"',),
    bool: ('t', 'f'),