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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`
'SizeBytes': -1
            },
            'awsRegion': aws_stack.get_region(),
            'eventSource': 'aws:dynamodb'
        }
        records = [record]
        streams_enabled_cache = {}
        table_name = data.get('TableName')
        event_sources_or_streams_enabled = has_event_sources_or_streams_enabled(table_name, streams_enabled_cache)
        if action == '%s.UpdateItem' % ACTION_PREFIX:
            if response.status_code == 200 and event_sources_or_streams_enabled:
                existing_item = self._thread_local('existing_item')
                record['eventName'] = 'INSERT' if not existing_item else 'MODIFY'
                updated_item = find_existing_item(data)
                if not updated_item:
                    return
                record['dynamodb']['Keys'] = data['Key']
                if existing_item:
                    record['dynamodb']['OldImage'] = existing_item
                record['dynamodb']['NewImage'] = updated_item
                record['dynamodb']['SizeBytes'] = len(json.dumps(updated_item))
        elif action == '%s.BatchWriteItem' % ACTION_PREFIX:
            records = self.prepare_batch_write_item_records(record, data)
            for record in records:
                event_sources_or_streams_enabled = (event_sources_or_streams_enabled or
                    has_event_sources_or_streams_enabled(record['eventSourceARN'], streams_enabled_cache))
        elif action == '%s.TransactWriteItems' % ACTION_PREFIX:
            records = self.prepare_transact_write_item_records(record, data)
            for record in records:
                event_sources_or_streams_enabled = (event_sources_or_streams_enabled or