Add documentation on installing the Perforce trigger script.
Review Request #12979 — Created April 21, 2023 and submitted
This updates the Perforce installation docs to discuss how to install
the Perforce trigger script for checking review request approval and
auto-closing review requests.
It provides a walkthrough, covering RBTools installation, script
download and customization, and installing it via
Built the docs and viewed them in the docs UI. Checked for spelling
errors, build errors, and bad links.