Add torchscript test for io image stuff

[NicolasHug]

All of our io stuff supports torchscript but somehow, we never properly tested for that. This PR adds tests for all the relevant APIs form image.py. I'm ignoring the video stuff.

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/vision/8313

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❌ 16 New Failures, 18 Unrelated Failures

As of commit 460c222 with merge base eb815ae ():

NEW FAILURES - The following jobs have failed:

• CMake / macos (macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• CMake / macos (macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• CMake / windows (windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• CMake / windows (windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-macos (3.10, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-macos (3.11, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-macos (3.12, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-macos (3.8, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-macos (3.8, macos-m1-stable) / macos-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-macos (3.9, macos-12) / macos-job (gh)
  The process '/usr/local/bin/git' failed with exit code 128
• Tests / unittests-windows (3.10, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.11, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.12, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.8, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.8, windows.g5.4xlarge.nvidia.gpu, cuda, 11.8) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128
• Tests / unittests-windows (3.9, windows.4xlarge, cpu) / windows-job (gh)
  The process 'C:\Program Files\Git\cmd\git.exe' failed with exit code 128

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• CMake / linux (linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• CMake / linux (linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Docs / build / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Lint / c-source / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Lint / python-types / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.10, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.11, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.12, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.8, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.8, linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Prototype tests on Linux / unittests-prototype (3.9, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-extended / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.10, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.11, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.12, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.8, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.8, linux.g5.4xlarge.nvidia.gpu, cuda, 11.8) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128
• Tests / unittests-linux (3.9, linux.12xlarge, cpu) / linux-job (gh)
  The process '/usr/bin/git' failed with exit code 128

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[vfdev-5]

lgtm

[github-actions]

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