ci: post comment on RollPyTorch tracker issue upon build failure

[ashay]

Now that the RollPyTorch tracker issue exists, we can automate the job
of notifying folks of failures instead of having to do it manually.
This patch adds a step to the workflow to post such a message.

[ashay]

The comment would look like this:

The RollPyTorch action has failed. See CI log for details.

The following information may come handy when fixing the code.

torch version: 2.0.0.dev20221216
torch commit hash: 2bd3fbe2e6b42f3c8f7eea443c89b515cb1981f1
torchvision version: 0.15.0.dev20221216