doc: add allowed info strings to style guide

This commit adds the list of agreed-upon info strings to the
documentation style guide to aid with future development and
maintenance.

Refs: https://github.com/nodejs/node/pull/33510
Refs: https://github.com/nodejs/node/pull/33507
Refs: https://github.com/nodejs/node/pull/33483
Refs: https://github.com/nodejs/node/pull/33531
Refs: https://github.com/nodejs/node/pull/33542
Refs: https://github.com/nodejs/node/pull/33028
Refs: https://github.com/nodejs/node/pull/33548
Refs: https://github.com/nodejs/node/pull/33486

PR-URL: https://github.com/nodejs/node/pull/34024


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>