Update Apps for JP4.6.2

[kevhsu-k]

Issue #, if available:

Description of changes:

• This is a PR for JP4.6.1
• Three OpenGPU apps (ONNX2TRT, ONNX, Pytorch) are slightly modified. Docker image using r32.7.
• For Tensorflow OpenGPU, it is more complicated though.
  • It requires upgrading tf version from tf2.4 to tf2.7. Detailed description on how to export tf-trt8 model is described inside README_JP461.md
  • TF24 app and TF27 app are split into two independent apps.
  • Moving the code back to git repository.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[SuryaKari]

Me and Mansi are reviewing this