treewide: Change URLs to HTTPS

Lots of URLs were HTTP redirect to HTTPS. Changed those and checked them
if there's actual content. Inspired by
https://github.com/NixOS/nixpkgs/issues/60004

pkgs/development/libraries/faac/default.nix

@@ -30,7 +30,7 @@ stdenv.mkDerivation rec {
 
   meta = {
     description = "Open source MPEG-4 and MPEG-2 AAC encoder";
-    homepage    = http://www.audiocoding.com/faac.html;
+    homepage    = https://www.audiocoding.com/faac.html;
     license     = licenses.unfreeRedistributable;
     maintainers = with maintainers; [ codyopel ];
     platforms   = platforms.all;