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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

Using node.js AWS SDK function `getObject` returns object with `0` bytes using 4566 port. 
On port 4572 it works fine.

# Steps to reproduce

## Command used to start LocalStack

```
  localstack:
    image: localstack/localstack
    networks:
      - localstack-network
    ports:
      - 4566:4566
      - 4572:4572
      - 8080:8080
    environment:
      - DEBUG=1
      - HOSTNAME_EXTERNAL=localstack
      - SERVICES=sqs,lambda,cloudwatch,s3,iam,ec2,stepfunctions,cloudwatchlogs
      - LAMBDA_REMOTE_DOCKER=false
      - LAMBDA_EXECUTOR=docker
      - LAMBDA_DOCKER_NETWORK=localstack-network
      - AWS_ACCESS_KEY_ID=123
      - AWS_SECRET_ACCESS_KEY=xyz
      - DEFAULT_REGION=us-east-1
      - DOCKER_HOST=unix:///var/run/docker.sock
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - /tmp/localstack:/tmp/localstack
```

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

```
export const s3 = new AWS.S3({
  endpoint: `http://localhost:4566`,
  s3ForcePathStyle: true,
  sslEnabled: false
});

const { Body } = await s3.getObject({
 Bucket: 'bucket',
 Key: 'file.json'
}).promise();
```
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 result[0] == 'monitoring':
        result = 'cloudwatch', config.PORT_CLOUDWATCH
    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):
    if(to_bytes('key=') in data_bytes):
        return True
    if(to_bytes('Content-Disposition: form-data') in data_bytes and to_bytes('name="key"') in data_bytes):
        return True
    return False
def serve_health_endpoint(method, path, data):
    if method == 'GET':
        reload = 'reload' in path
        return plugins.get_services_health(reload=reload)
    if method == 'PUT':
        data = json.loads(to_str(data))
        plugins.set_services_health(data)
        return {'status': 'OK'}
def get_port_from_custom_rules(method, path, data, headers):