Improvements for readability in ADVANCED-USERS.md

[mikekgfb]

• Various spelling corrections
• Remove empty performance tables
• Remove CONTRIBUTING section that is covered in the project root README

[pytorch-bot[bot]]

:link: Helpful Links

:test_tube: See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/torchchat/1393

• :page_facing_up: Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

:white_check_mark: No Failures

As of commit bceed0f68863608d5e6869ca12f9dea779c7d1e3 with merge base 6895a18b994bf910c3d6d6c9d55c93504448ec90 (): :green_heart: Looks good so far! There are no failures yet. :green_heart:

This comment was automatically generated by Dr. CI and updates every 15 minutes.