Torch upgrade

[nargokul]

Issue #, if available:

Description of changes:
Upgrade torch and torchvision versions

• Also contains a test skipping because the pytorch test seems to be failing after the new RBA update which is pointing to a ECR URI that is no longer supported. https://github.com/aws/deep-learning-containers/blob/master/available_images.md. Will create a separate item to track this.
• • 30fe0ee

Testing done:
Unit and Integ tests

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[kingroryg]

LGTM!