training stuck with multi gpu and dali training loader
**Describe the bug**

Training get stuck when using ddp and dali loader together.


![image](https://user-images.githubusercontent.com/1567200/200734230-11aff089-a2e8-402f-9396-007c74159b93.png)

the usage of second gpu is zero. 

it works if I change `use_dali` to False

**Steps/Code to reproduce bug**

I follow the asr finetuing tutorial (https://github.com/NVIDIA/NeMo/blob/main/tutorials/asr/ASR_CTC_Language_Finetuning.ipynb), and change `devices=2`, `strategy='ddp'`.

```
trainer = ptl.Trainer(devices=2, 
                      accelerator=accelerator, 
                      strategy='ddp',
                      max_epochs=EPOCHS, 
                      accumulate_grad_batches=1,
                      enable_checkpointing=False,
                      logger=False,
                      log_every_n_steps=5,
                      check_val_every_n_epoch=10)

```

also, I change  `cfg.train_ds.use_dali=True`

Any idea?
