Contributor Book: Fix the link of primitive types in the "Serializati…

…on" page (#2362)

* Fix link of primitive types in Serialization page

* Change the intra-doc link to an external one
  Keep consistent with other links in the book by referring to a
  specific commit instead of "main". Since there is no single commit
  used by all the links, simply pick the latest commit being used in
  pages under the "project-architecture" directory.

* Better the wording of the link name

* Replace the specific commit in the URL with "main"

Make the change based on review feedback.

contributor-book/src/project-architecture/serialization.md

@@ -40,8 +40,8 @@ which field is a parameter or a constant, or we assume that each field implement
 
 The second solution was chosen as it simplifies the code generation and reduces the size of the user
 API. This means that the `Module` trait should be implemented by
-[primitives types](./burn-core/src/module/param/primitive.rs). The following diagrams highlight the
-main types and traits used in the solution.
+[primitive types](https://github.com/tracel-ai/burn/blob/main/crates/burn-core/src/module/param/primitive.rs).
+The following diagrams highlight the main types and traits used in the solution.
 
 <div align="center">
 <h4>Module Serialization Types</h4>