Update filter.filterfailedexception.xml

Co-authored-by: Jordi Kroon <jordi@jordikroon.nl>

Author: lacatoire

reference/filter/filter.filterfailedexception.xml

@@ -25,7 +25,7 @@
 
      <ooclass>
       <modifier>extends</modifier>
-      <classname>Filter\FilterException</classname>
+      <exceptionname>Filter\FilterException</exceptionname>
      </ooclass>
 
      <classsynopsisinfo role="comment">&InheritedProperties;</classsynopsisinfo>