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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();
```
result = BaseHTTPRequestHandler.parse_request(self)
        if not result:
            return result
        if sys.version_info[0] >= 3:
            return result
        
        
        expect = self.headers.get('Expect', '')
        if (expect.lower() == '100-continue' and
                self.protocol_version >= 'HTTP/1.1' and
                self.request_version >= 'HTTP/1.1'):
            if self.request_version != 'HTTP/0.9':
                self.wfile.write(('%s %d %s\r\n' %
                    (self.protocol_version, 100, 'Continue')).encode('latin1', 'strict'))
                self.end_headers()
        return result
    def do_GET(self):