Update free-programming-books-nl.md (#4058)

free-programming-books-nl.md

@@ -10,7 +10,7 @@
 
 #### Symfony
 
-* [Symfony 5: Snel van start](https://symfony.com/doc/5.0/the-fast-track/nl/index.html)
+* [Symfony 5: Snel van start](https://symfony.com/doc/current/the-fast-track/nl/index.html)
 
 
 ### Python