Auto merge of #147660 - notriddle:stringdex-002, r=GuillaumeGomez

rustdoc-search: stringdex 0.0.2

Two index format tweaks that reduce the size of the standard library, compiler, and wordnet dictionary when I test it.

CC rust-lang/rust#146048

FF Profiler output: https://share.firefox.dev/4onH5xP

Preview: https://notriddle.com/rustdoc-html-demo-12/stringdex-002/std/index.html

Author: bors