[docs] Update install docs for PyTorch

[ervteng]

Proposed change(s)

Update install documentation for PyTorch with working instructions for Windows. Rather than repeating the commands in our docs, more explicitly link to PyTorch official documentation.

Types of change(s)

• Bug fix
• New feature
• Code refactor
• Breaking change
• Documentation update
• Other (please describe)

Checklist

• Added tests that prove my fix is effective or that my feature works
• Updated the changelog (if applicable)
• Updated the documentation (if applicable)
• Updated the migration guide (if applicable)

Other comments