Fix lint issues

[AntoineSimoulin]

Fix linting issues torchvision/utils.py:369: error: Incompatible types in assignment (expression has type "list[tuple[int, int, int]]", variable has type "list[str | tuple[int, int, int]] | str | tuple[int, int, int] | None").

Also fix failing tests pytest test/test_utils.py -vvv -k "test_draw_segmentation_masks_errors" to match expected error message "colors must be a tuple or a string, or a list thereof".

[pytorch-bot]

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✅ You can merge normally! (1 Unrelated Failure)

As of commit 7de543d with merge base bddc4d8 ():

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

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

• CMake / windows (windows.g5.4xlarge.nvidia.gpu, cuda, 12.6) / windows-job (gh) (trunk failure)
  Process completed with exit code 1.

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[github-actions]

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