### 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_
java_tool_opts = environment.get("JAVA_TOOL_OPTIONS", "")
    if agent_flag not in java_tool_opts:
        java_tool_opts += f" {agent_flag}"
    result.env_updates["JAVA_TOOL_OPTIONS"] = java_tool_opts.strip()
    
    
    
    
    
    
    
    if _is_java8_lambda(context.lambda_function):
        java_opts = environment.get("_JAVA_OPTIONS", "")
        java_opts += " -Xshare:off"
        result.env_updates["_JAVA_OPTIONS"] = java_opts.strip()
    
    log_disabled = environment.get(THUNDRA_AGENT_LOG_DISABLE_ENV_VAR_NAME)
    if not log_disabled:
        result.env_updates[THUNDRA_AGENT_LOG_DISABLE_ENV_VAR_NAME] = "false"
    
    result.env_updates[THUNDRA_APIKEY_ENV_VAR_NAME] = _get_apikey(environment)
    
    
    
    
    
    
    result.files_to_add["agent_path"] = THUNDRA_JAVA_AGENT_LOCAL_PATH
    return result
def _ensure_node_agent_initialized():