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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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self.next_port = (self.next_port + 1) % self.max_port
        
        LOG.debug('Priming docker container with runtime "%s" and arn "%s".', runtime, func_arn)
        container_info = self.prime_docker_container(runtime, func_arn, env_vars.items(), lambda_cwd)
        
        
        
        exec_env_vars = ' '.join(['-e {}="${}"'.format(k, k) for (k, v) in env_vars.items()])
        if not command:
            command = '%s %s' % (container_info.entry_point, handler)
        
        copy_command = ''
        docker_cmd = self._docker_cmd()
        event_file = os.path.join(lambda_cwd, LAMBDA_EVENT_FILE)
        if not has_been_invoked_before and config.LAMBDA_REMOTE_DOCKER:
            
            copy_command = '%s cp "%s/." "%s:/var/task";' % (docker_cmd, lambda_cwd, container_info.name)
        elif os.path.exists(event_file):
            
            copy_command = '%s cp "%s" "%s:/var/task";' % (docker_cmd, event_file, container_info.name)
        cmd = (
            '%s'
            ' %s exec'
            ' %s'  
            ' %s'  
            ' %s'  
        ) % (copy_command, docker_cmd, exec_env_vars, container_info.name, command)
        LOG.debug('Command for docker-reuse Lambda executor: %s' % cmd)
        return cmd
    def startup(self):