Fix error log message for change event dispatcher

Change-Id: Ieffd61a847d0284b85c43c99f3e66eafc3daa8de
diff --git a/hooks-its/src/main/java/com/googlesource/gerrit/plugins/hooks/workflow/GerritHookFilter.java b/hooks-its/src/main/java/com/googlesource/gerrit/plugins/hooks/workflow/GerritHookFilter.java
index 83c1544..10b13d6 100644
--- a/hooks-its/src/main/java/com/googlesource/gerrit/plugins/hooks/workflow/GerritHookFilter.java
+++ b/hooks-its/src/main/java/com/googlesource/gerrit/plugins/hooks/workflow/GerritHookFilter.java
@@ -175,7 +175,7 @@
         log.info("Event " + event + " not recognised and ignored");
       }
     } catch (Throwable e) {
-      log.error("Event " + e + " processing failed", e);
+      log.error("Event " + event + " processing failed", e);
     }
   }