### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

The use case I have in mind is to run Node 16.x Lambdas - the default container registry is `lambci/lambda` which is effectively abandoned. [Not even Node 14.x has been published](https://github.com/lambci/docker-lambda/pull/330). However, switching the registry over to [`amazon/aws-lambda-nodejs`](https://hub.docker.com/r/amazon/aws-lambda-nodejs) still fails to pull the container, since localstack is looking for the tag `nodejs16.x`. I'd like to be able to specify that if the runtime is `nodejs16.x` it just looks for tag `16`.

### 🧑‍💻 Implementation

_No response_

### Anything else?

_No response_
super(LambdaExecutorReuseContainers, self).__init__()
        
        self.docker_container_lock = threading.RLock()
        
        
        
        
        self.next_port = 0
        self.max_port = LAMBDA_SERVER_UNIQUE_PORTS
        self.port_offset = LAMBDA_SERVER_PORT_OFFSET
    def execute_in_container(
        self,
        lambda_function: LambdaFunction,
        inv_context: InvocationContext,
        stdin=None,
        background=False,
    ) -> Tuple[bytes, bytes]:
        func_arn = lambda_function.arn()
        lambda_cwd = lambda_function.cwd