Document Triton dependency for the release process (#109296)
Document triton dependency for the Pytorch Release
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### <samp>🤖 Generated by Copilot at e9773f0</samp>
Add documentation for Triton dependency in `RELEASE.md`. The documentation covers how to install and use Triton for various PyTorch builds and platforms.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/109296
Approved by: https://github.com/malfet
