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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description
When `mountCode: true` for a serverless.yml deployment to localstack on Windows, Localstack mounts the wrong path.
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## Expected behavior
Docker expects the Windows client path value of the `-v` flag to begin with `/host_mtn/`.
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## Actual behavior
Localstack does not add this to the Windows client path. This causes the volume sharing to fail. Once one tries to invoke a lambda without the proper volume sharing, the lambda fails with an error along the lines of "can't find no module 'lambda_name'".
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# Steps to reproduce
1. In your `serverless.yml` set `mountCode: true` 
2. In your `docker-compose.yml` set the environment variable `LAMBDA_REMOTE_DOCKER: "0"` for the localstack container
3. Deploy some test lambda to the localstack container
4. Attempt to invoke with `awslocal lambda invoke --function-name LAMBDA_NAME out.txt` and replace LAMBDA_NAME with the name of your test lambda.
5. Note the invocation failure.

## Command used to start LocalStack
Started via a `docker-compose.yml` file. Pretty basic stuff.
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## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
Just the `awslocal` invoke command outlined above.
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dlq_sent = None
            try:
                result = self._execute(func_arn, func_details, event, context, version)
            except Exception as e:
                raised_error = e
                if asynchronous:
                    if get_from_event(event, 'eventSource') == EVENT_SOURCE_SQS:
                        sqs_queue_arn = get_from_event(event, 'eventSourceARN')
                        if sqs_queue_arn:
                            
                            dlq_sent = sqs_error_to_dead_letter_queue(sqs_queue_arn, event, e)
                    else:
                        
                        lambda_error_to_dead_letter_queue(func_details, event, e)
                raise e
            finally:
                self.function_invoke_times[func_arn] = invocation_time
                callback and callback(result, func_arn, event, error=raised_error, dlq_sent=dlq_sent)
            
            return result
        
        if asynchronous:
            LOG.debug('Lambda executed in Event (asynchronous) mode, no response will be returned to caller')
            FuncThread(do_execute).start()
            return None, 'Lambda executed asynchronously.'
        return do_execute()
    def _execute(self, func_arn, func_details, event, context=None, version=None):
        """ This method must be overwritten by subclasses. """
        raise Exception('Not implemented.')
    def startup(self):