[Backend Tester] Add pointwise op tests

[GregoryComer]

Add tests for various element-wise ops.

[GregoryComer]

Stack from ghstack (oldest at bottom):

• [Backend Tester] Add upsample tests #12856
• [Backend Tester] Add more pointwise op tests #12855
• -> [Backend Tester] Add pointwise op tests #12854
• [Backend Tester] Add reduction op tests #12853
• [Backend Tester] Add index_put and index_select tests #12852

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/12854

• 📄 Preview Python docs built from this PR

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❌ 1 New Failure, 1 Pending

As of commit e346d17 with merge base 9deb51b ():

NEW FAILURE - The following job has failed:

• pull / unittest-editable / macos / macos-job (gh)
  Can't find 'action.yml', 'action.yaml' or 'Dockerfile' under '/Users/ec2-user/runner/_work/executorch/executorch/test-infra/.github/actions/check-disk-space'. Did you forget to run actions/checkout before running your local action?

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

[GregoryComer]

Macos CI failure is unrelated.