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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

When running with dynamodb errors set to 1.0 and performing basically any kind of request, I see the following in the console: 

```
localstack_main | 2021-01-22T22:14:37:WARNING:localstack.utils.server.http2_server: Error in proxy handler for request POST http://localhost:4566/: 'ProxyListenerDynamoDB' object has no attribute 'error_response_throughput' Traceback (most recent call last):
localstack_main |   File "/opt/code/localstack/localstack/utils/server/http2_server.py", line 107, in index
localstack_main |     raise result
localstack_main |   File "/opt/code/localstack/localstack/utils/bootstrap.py", line 581, in run
localstack_main |     result = self.func(self.params)
localstack_main |   File "/opt/code/localstack/localstack/utils/async_utils.py", line 28, in _run
localstack_main |     return fn(*args, **kwargs)
localstack_main |   File "/opt/code/localstack/localstack/services/generic_proxy.py", line 605, in handler
localstack_main |     response = modify_and_forward(method=method, path=path_with_params, data_bytes=data, headers=headers,
localstack_main |   File "/opt/code/localstack/localstack/services/generic_proxy.py", line 373, in modify_and_forward
localstack_main |     listener_result = listener.forward_request(method=method,
localstack_main |   File "/opt/code/localstack/localstack/services/edge.py", line 105, in forward_request
localstack_main |     return do_forward_request(api, method, path, data, headers, port=port)
localstack_main |   File "/opt/code/localstack/localstack/services/edge.py", line 116, in do_forward_request
localstack_main |     result = do_forward_request_inmem(api, method, path, data, headers, port=port)
localstack_main |   File "/opt/code/localstack/localstack/services/edge.py", line 136, in do_forward_request_inmem
localstack_main |     response = modify_and_forward(method=method, path=path, data_bytes=data, headers=headers,
localstack_main |   File "/opt/code/localstack/localstack/services/generic_proxy.py", line 373, in modify_and_forward
localstack_main |     listener_result = listener.forward_request(method=method,
localstack_main |   File "/opt/code/localstack/localstack/services/dynamodb/dynamodb_listener.py", line 97, in forward_request
localstack_main |     return self.error_response_throughput()
localstack_main | AttributeError: 'ProxyListenerDynamoDB' object has no attribute 'error_response_throughput'
```

which seems like a mistake. It looks like we get one of those for every request.

## Expected behavior

I wouldn't expect the console to print anything

# Steps to reproduce

I made #3501 to simplify reproduction. Basically just pull that, pull the latest docker image, run `./example/run.sh`.

## Command used to start LocalStack

`docker-compose up`
fix_headers_for_updated_response(response)
            return response
        return True
    def return_response(self, method, path, data, headers, response):
        if path.startswith('/shell') or method == 'GET':
            return
        data = json.loads(to_str(data))
        
        if data and 'TableName' in data and 'KeySchema' in data:
            TABLE_DEFINITIONS[data['TableName']] = data
        if response._content:
            
            content_replaced = re.sub(
                r'("TableArn"|"LatestStreamArn"|"StreamArn")\s*:\s*"arn:aws:dynamodb:ddblocal:([^"]+)"',
                r'\1: "arn:aws:dynamodb:%s:\2"' % aws_stack.get_region(),
                to_str(response._content)
            )
            if content_replaced != response._content:
                response._content = content_replaced
                fix_headers_for_updated_response(response)
        action = headers.get('X-Amz-Target')
        if not action:
            return
        
        record = {
            'eventID': '1',
            'eventVersion': '1.1',
            'dynamodb': {
                'ApproximateCreationDateTime': time.time(),
                'StreamViewType': 'NEW_AND_OLD_IMAGES',