llm.import_ckpt cannot run directly
When I run the following code directly, it seems there is a deadlock inside with spawn multiple processes. The follow code is exactly the same as just use llm.import_ckpt directly as a main function. 

```
from nemo.collections import llm
import nemo_run as run

ckpt_import = run.Partial(
    llm.import_ckpt,
    model=run.Config(llm.LlamaModel, config=run.Config(llm.Llama31Config8B)),
    source=f'hf://{model_path}',
    overwrite=True,  
)
local_executor = run.LocalExecutor()
run.run(ckpt_import, executor=local_executor, direct=True)
```

However, if I remove direct=True, and use the local_executor to run the importer, the checkpoint can be successfully transformed. 
```
run.run(ckpt_import, executor=local_executor) # can sucess
```

Can you let me know whether this behavior is expected or there is a bug within the ModelConnector? 

Thank you!
