Add note to include Student's domain in the Wiki

Author: fmcarvalho

README.md

@@ -50,4 +50,6 @@ according to the following design:
 2. Implement unit tests for a domain model of your choice that includes at least
    two associations, with one having a multiple multiplicity relationship.
    You may use any AI tool, such as Copilot, ChatGPT, or others, to assist you
-   in implementing these unit tests and the domain model.
+   in implementing these unit tests and the domain model.
+
+   You must include your chosen domain here: https://github.com/isel-leic-ave/jsonoy/wiki/Student-Domain-Selections