### 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_
tags = {"env": "testing"}
        kwargs = {
            "FunctionName": func_name,
            "Runtime": LAMBDA_RUNTIME_PYTHON37,
            "Handler": LAMBDA_DEFAULT_HANDLER,
            "Role": LAMBDA_TEST_ROLE,
            "KMSKeyArn": kms_key_arn,
            "Code": {
                "ZipFile": create_lambda_archive(
                    load_file(TEST_LAMBDA_PYTHON_ECHO), get_content=True
                )
            },
            "Timeout": 3,
            "VpcConfig": vpc_config,
            "Tags": tags,
            "Environment": {"Variables": {"foo": "bar"}},
        }
        result = lambda_client.create_function(**kwargs)
        function_arn = result["FunctionArn"]
        assert testutil.response_arn_matches_partition(lambda_client, function_arn)
        partial_function_arn = ":".join(function_arn.split(":")[3:])
        
        for func_ref in [func_name, function_arn, partial_function_arn]:
            rs = lambda_client.get_function(FunctionName=func_ref)
            assert rs["Configuration"].get("KMSKeyArn", "") == kms_key_arn
            assert rs["Configuration"].get("VpcConfig", {}) == vpc_config
            assert rs["Tags"] == tags
        
        lambda_client.delete_function(FunctionName=func_name)
        with pytest.raises(Exception) as exc: