### 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_
f = os.path.join(config.dirs.tmp, short_uid())
        TMP_FILES.append(f)
        return f
    @staticmethod
    def inject_endpoints_into_env(env_vars: Dict[str, str]):
        env_vars = env_vars or {}
        main_endpoint = get_main_endpoint_from_container()
        if not env_vars.get("LOCALSTACK_HOSTNAME"):
            env_vars["LOCALSTACK_HOSTNAME"] = main_endpoint
        return env_vars
class OutputLog:
    __slots__ = ["_stdout", "_stderr"]
    def __init__(self, stdout, stderr):