docs: update link URLs for temporary settings page

Created by: courier-new

Fixes broken links to the TemporarySettings files in our docs page about temporary settings. The files referenced were moved from the web folder to the shared folder at some point, but the links weren't updated to match. The line references to highlight didn't match up, either. Since the lines can be expected to be much less stable, I omitted them in the case of the hook file and only provided the starting line in the case of the schema interface definition.

Test plan

Just fixes for broken docs links.