Add `-debug` suffix to trunk libtorch builds (#102764)
Cause that's what they are according to
https://github.com/pytorch/pytorch/blob/30558c28966a31f9147d260176837f2804ab8d66/.ci/pytorch/build.sh#L307
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### <samp>🤖 Generated by Copilot at 40cd88d</samp>
> _`libtorch` debug_
> _Build with symbols for Linux_
> _Winter of errors_
Pull Request resolved: https://github.com/pytorch/pytorch/pull/102764
Approved by: https://github.com/atalman
