Video tests SEGFAULT if torchvision is build against ffmpeg >= 4.4

[pmeier]

• ffmpeg==4.4.2: https://github.com/pytorch/vision/actions/runs/4230815953/jobs/7348586970#step:10:278
• ffmpeg==5.1.2: https://github.com/pytorch/vision/actions/runs/4224709135/jobs/7336018796#step:10:285

This went undetected, since we accidentally don't build against ffmpeg in our unittest workflows since Nov 2022. See #7295.