Used a deprecated directive

Author: javiereguiluz

bundles/inheritance.rst

@@ -4,7 +4,7 @@
 How to Use Bundle Inheritance to Override Parts of a Bundle
 ===========================================================
 
-.. caution::
+.. deprecated:: 3.4
 
     Bundle inheritance is deprecated since Symfony 3.4 and will be removed in
     4.0, but you can :doc:`override any part of a bundle </bundles/override>`