document that `torch.triangular_solve` has optional out= parameter (#63253)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63253
Fixes #57955
Test Plan: Imported from OSS
Reviewed By: malfet
Differential Revision: D30312134
Pulled By: dagitses
fbshipit-source-id: 4f484620f5754f4324a99bbac1ff783c64cee6b8
