Update Further reading link for consistency

Replace dead `Susan Potter` link and replace with `Rommel Martinez` reference from `[nix/en]`.
Was unable to find archived version of Potter link. Using Nix Manual, Fisher example, and Martinez
intro as the three `Further Reading` references across translations.

sv-se/nix-sv.html.markdown

@@ -364,5 +364,5 @@ with builtins; [
 * [James Fisher - Nix by example - Part 1: The Nix expression language]
   (https://medium.com/@MrJamesFisher/nix-by-example-a0063a1a4c55)
 
-* [Susan Potter - Nix Cookbook - Nix By Example]
-  (http://funops.co/nix-cookbook/nix-by-example/)
+* [Rommel Martinez - A Gentle Introduction to the Nix Family]
+  (https://web.archive.org/web/20210121042658/https://ebzzry.io/en/nix/#nix)