### 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_
DockerContainerStatus,
    PortMappings,
)
from localstack.utils.docker_utils import DOCKER_CLIENT
from localstack.utils.run import FuncThread
LAMBDA_EXECUTOR_JAR = INSTALL_PATH_LOCALSTACK_FAT_JAR
LAMBDA_EXECUTOR_CLASS = "cloud.localstack.LambdaExecutor"
LAMBDA_HANDLER_ENV_VAR_NAME = "_HANDLER"
EVENT_FILE_PATTERN = "%s/lambda.event.*.json" % config.dirs.tmp
LAMBDA_SERVER_UNIQUE_PORTS = 500
LAMBDA_SERVER_PORT_OFFSET = 5000
LAMBDA_API_UNIQUE_PORTS = 500
LAMBDA_API_PORT_OFFSET = 9000
MAX_ENV_ARGS_LENGTH = 20000
STAY_OPEN_API_PORT = 9001
INTERNAL_LOG_PREFIX = "ls-daemon: "
LOG = logging.getLogger(__name__)
MAX_CONTAINER_IDLE_TIME_MS = 600 * 1000
EVENT_SOURCE_SQS = "aws:sqs"
LAMBDA_CONCURRENCY_LOCK = {}
DOCKER_TASK_FOLDER = "/var/task"
ALLOWED_IDENTITY_FIELDS = ["cognitoIdentityId", "cognitoIdentityPoolId"]
LambdaEvent = Union[Dict[str, Any], str, bytes]
HOOKS_ON_LAMBDA_DOCKER_SEPARATE_EXECUTION = "localstack.hooks.on_docker_separate_execution"
HOOKS_ON_LAMBDA_DOCKER_REUSE_CONTAINER_CREATION = (
    "localstack.hooks.on_docker_reuse_container_creation"
)
on_docker_separate_execution = hook_spec(HOOKS_ON_LAMBDA_DOCKER_SEPARATE_EXECUTION)
on_docker_reuse_container_creation = hook_spec(HOOKS_ON_LAMBDA_DOCKER_REUSE_CONTAINER_CREATION)
class InvocationException(Exception):