Using Kinetics400 from references raises a deprecation warning

🐛 Describe the bug

Using Kinetics400 from references leads to a deprecation warning. The fastest way to reproduce:

torchrun --nproc_per_node=8 train.py --data-path /datasets01/kinetics/070618/ --train-dir=val_avi-480p --val-dir=val_avi-480p --batch-size=64 --sync-bn --test-only --weights R2Plus1D_18_Weights.DEFAULT --cache-dataset

./vision/torchvision/io/video.py:160: UserWarning: The pts_unit 'pts' gives wrong results and will be removed in a follow-up version. Please use pts_unit 'sec'.
  warnings.warn(

It seems this is due to the following line:
https://github.com/pytorch/vision/blob/b7c59a086f4e45b8e5e799084e97cca775977a3b/torchvision/datasets/video_utils.py#L327

Which calls the method with the default parameter for pts_unit="pts" which is deprecated:
https://github.com/pytorch/vision/blob/b7c59a086f4e45b8e5e799084e97cca775977a3b/torchvision/io/video.py#L155-L163

If the specific option is deprecated, TorchVision shouldn't be using the feature.

Versions

Latest main branch

cc @pmeier @YosuaMichael @bjuncek

Start in torchvision/datasets/video_utils.py at the Kinetics400 call around line 327, then read torchvision/io/video.py around lines 155-163 to understand the warning. Reproduce the issue with the provided torchrun command and verify that using Kinetics400 no longer emits the deprecated pts_unit warning.