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

doc/languages-frameworks/python.section.md

@@ -445,7 +445,7 @@ buildPythonPackage rec {
   };
 
   meta = with lib; {
-    homepage = "http://github.com/pytoolz/toolz/";
+    homepage = "https://github.com/pytoolz/toolz/";
     description = "List processing tools and functional utilities";
     license = licenses.bsd3;
     maintainers = with maintainers; [ fridh ];