dump ios test simulator logs on a failure (#82822)
### Description
This PR adds another step to `_ios-build-test.yml` to dump out the build and test logs to the mainline log in case of a failure.
### Issue
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### Testing
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Pull Request resolved: https://github.com/pytorch/pytorch/pull/82822
Approved by: https://github.com/malfet, https://github.com/seemethere
