Update README.md

Author: MitkoVtori

OOP/README.md

@@ -46,4 +46,5 @@
 | <a href="9.Decorators/Decorators - Exercise">Exercise: Decorators</a> |
 | ----------------------- |
 | <a href="A.Testing">Testing</a> |
+| -------------- |
 | <a href="A.Testing/Testing - Lab">Testing</a> |