using "!php/const:" with a colon isn't allowed anymore

Author: OskarStark

service_container/parameters.rst

@@ -253,8 +253,8 @@ Setting PHP constants as parameters is also supported:
     .. code-block:: yaml
 
         parameters:
-            global.constant.value: !php/const:GLOBAL_CONSTANT
-            my_class.constant.value: !php/const:My_Class::CONSTANT_NAME
+            global.constant.value: !php/const GLOBAL_CONSTANT
+            my_class.constant.value: !php/const My_Class::CONSTANT_NAME
 
     .. code-block:: xml