Rollup merge of #46010 - lnicola:escape-root, r=GuillaumeGomez
Rollup merge of #46010 - lnicola:escape-root, r=GuillaumeGomez

rustdoc: Escape doc root URLs

This fixes a small HTML injection issue.

GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,GBGamer/rust,graydon/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,graydon/rust