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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();
```
def __init__(self, port, forward_url=None, ssl=False, host=None, update_listener=None, quiet=False, params={}):
        FuncThread.__init__(self, self.run_cmd, params, quiet=quiet)
        self.httpd = None
        self.port = port
        self.ssl = ssl
        self.quiet = quiet
        if forward_url:
            if '://' not in forward_url:
                forward_url = 'http://%s' % forward_url
            forward_url = forward_url.rstrip('/')
        self.forward_base_url = forward_url
        self.update_listener = update_listener
        self.server_stopped = False
        
        self.protocol_version = params.get('protocol_version') or 'HTTP/1.1'
        self.listen_host = host or ''
    def run_cmd(self, params):
        try:
            self.httpd = ThreadedHTTPServer((self.listen_host, self.port), GenericProxyHandler)
            if self.ssl:
                
                combined_file, cert_file_name, key_file_name = GenericProxy.create_ssl_cert(serial_number=self.port)
                self.httpd.socket = ssl.wrap_socket(self.httpd.socket,
                    server_side=True, certfile=combined_file)
            self.httpd.my_object = self
            self.httpd.serve_forever()
        except Exception as e:
            if not self.quiet or not self.server_stopped:
                LOG.error('Exception running proxy on port %s: %s %s' % (self.port, e, traceback.format_exc()))
    def stop(self, quiet=False):