Tidy links, and lint (#2435)

Tidies up a number of things:

- Outdated links that redirect
- Dead links
- Remove unnecessary parameters eg "en" and "en-US"
- Shortened amazon, apps.apple.com, reddit links
- Removed trailing /
- Remove www (except for PG assets)
- Optimize unoptimized SVGs and remove xml declarations
- Lint yaml, md files

Co-Authored-By: Daniel Gray <dngray@privacyguides.org>

theme/assets/img/messengers/element.svg

@@ -1,2 +1 @@
-<?xml version="1.0" encoding="UTF-8"?>
 <svg width="128" height="128" version="1.1" viewBox="0 0 33.867 33.867" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.70556 0 0 .70556 -5.6444 -5.6444)" clip-rule="evenodd" fill="#0dbd8b" fill-rule="evenodd"><path d="m25.28 10.88c0-1.5906 1.2894-2.88 2.88-2.88 10.604 0 19.2 8.5961 19.2 19.2 0 1.5906-1.2894 2.88-2.88 2.88s-2.88-1.2894-2.88-2.88c0-7.4227-6.0173-13.44-13.44-13.44-1.5906 0-2.88-1.2894-2.88-2.88z"/><path d="m38.72 53.12c0 1.5906-1.2894 2.88-2.88 2.88-10.604 0-19.2-8.5961-19.2-19.2 0-1.5906 1.2894-2.88 2.88-2.88 1.5905 0 2.88 1.2894 2.88 2.88 0 7.4227 6.0173 13.44 13.44 13.44 1.5906 0 2.88 1.2894 2.88 2.88z"/><path d="m10.88 38.72c-1.5906 0-2.88-1.2894-2.88-2.88 0-10.604 8.5961-19.2 19.2-19.2 1.5906 0 2.88 1.2894 2.88 2.88 0 1.5905-1.2894 2.88-2.88 2.88-7.4227 0-13.44 6.0173-13.44 13.44 0 1.5906-1.2894 2.88-2.88 2.88z"/><path d="m53.12 25.28c1.5906 0 2.88 1.2894 2.88 2.88 0 10.604-8.5961 19.2-19.2 19.2-1.5906 0-2.88-1.2894-2.88-2.88 0-1.5905 1.2894-2.88 2.88-2.88 7.4227 0 13.44-6.0173 13.44-13.44 0-1.5906 1.2894-2.88 2.88-2.88z"/></g></svg>