### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

`PORTS_CHECK_DOCKER_IMAGE` is not configurable which prevents ECS tasks from running on air-gapped environment



### Expected Behavior

`PORTS_CHECK_DOCKER_IMAGE` can be configured via configuration option to allow use of any available image 

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

Run an ECS task in an environment where localstack/localstack is not available.

### Environment

```markdown
- OS: RHEL8
- Docker runtime version: Podman v4.2.0
- LocalStack: 1.3.1
```


### Anything else?

_No response_
if os.environ.get(port_env_name):
            port_number = os.environ.get(port_env_name)
        
        if len(parts) > 1:
            port_number = int(parts[-1])
        
        try:
            port_number = int(port_number)
        except Exception:
            port_number = 0
        result[service] = port_number
    return result
SERVICE_PORTS = parse_service_ports()
def populate_config_env_var_names():
    global CONFIG_ENV_VARS
    for key, value in DEFAULT_SERVICE_PORTS.items():
        clean_key = key.upper().replace("-", "_")
        CONFIG_ENV_VARS += [
            clean_key + "_BACKEND",
            clean_key + "_PORT_EXTERNAL",
            "PROVIDER_OVERRIDE_" + clean_key,
        ]
    
    CONFIG_ENV_VARS += [
        "LOCALSTACK_" + v for v in CONFIG_ENV_VARS if not v.startswith("LOCALSTACK_")
    ]
    CONFIG_ENV_VARS = list(set(CONFIG_ENV_VARS))
populate_config_env_var_names()
def service_port(service_key: str, external: bool = False) -> int: