Fix int/float typing in video_utils.py

[bryant1410]

Many of these types that accept ints are actually already accepting floats.

Also, remove old-style unnecessary conversion to float.

[pytorch-bot]

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✅ You can merge normally! (2 Unrelated Failures)

As of commit 96031fa with merge base 0be6c7e ():

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• Lint / bc (gh)
  Process completed with exit code 1.

BROKEN TRUNK - The following job failed but was present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• Build Windows Conda / pytorch/vision / conda-py3_8-cpu (gh)
  Process completed with exit code 1.

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[bryant1410]

I now converted the Union[int, float] into float, following https://stackoverflow.com/a/50928627/1165181.

[bryant1410]

I don't understand the test failures. Are they false positives?

[NicolasHug]

Thank you @bryant1410