In [this PR](https://github.com/localstack/localstack/pull/1200/files) we introduced a new way of starting S3 in a separate process.

In the meantime, the service startup has been significantly reworked, and it seems that we can integrate the S3 starter into the [`multiserver.py`](https://github.com/localstack/localstack/blob/master/localstack/utils/server/multiserver.py) based loading approach that loads multiple APIs in a single process, for performance reasons. We should look into that.
self.assertEqual(response.status_code, 200)
        self.assertEqual(response.text, 'This is the error document')
        
        self.s3_client.delete_object(Bucket=bucket_name, Key='error.html')
        self.s3_client.delete_bucket(Bucket=bucket_name)
        
        bucket_name = 'test-bucket-%s' % short_uid()
        self.s3_client.create_bucket(Bucket=bucket_name)
        self.s3_client.put_bucket_website(
            Bucket=bucket_name,
            WebsiteConfiguration={'IndexDocument': {'Suffix': 'index.html'}}
        )
        url = self.s3_client.generate_presigned_url(
            'get_object', Params={'Bucket': bucket_name, 'Key': 'nonexistent'}
        )
        response = requests.get(url, verify=False)
        self.assertEqual(response.status_code, 404)
        
        self.s3_client.delete_bucket(Bucket=bucket_name)
        
        bucket_name = 'test-bucket-%s' % short_uid()
        self.s3_client.create_bucket(Bucket=bucket_name)
        url = self.s3_client.generate_presigned_url(
            'get_object', Params={'Bucket': bucket_name, 'Key': 'nonexistent'}
        )
        response = requests.get(url, verify=False)
        self.assertEqual(response.status_code, 404)
        
        self.s3_client.delete_bucket(Bucket=bucket_name)
    def test_s3_event_notification_with_sqs(self):