Allow 2D numpy arrays as inputs for to_image

[mantasu]

Closes #8255

if the input is 2D, numpy.atleast_3d simply adds an extra dimension to the end which can then be safely permuted.

cc @vfdev-5

[pytorch-bot]

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✅ You can merge normally! (2 Unrelated Failures)

As of commit 3100374 with merge base 8e71207 ():

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

• CMake / windows (windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
  ##[error]The operation was canceled.

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)
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[NicolasHug]

Thanks for the report and for the PR @mantasu ! I took the liberty to push a small unittest to your PR. LGTM, I'll merge when the CI is green. Thank you!