Add ignore line

SpigotCore_Main/src/de/steamwar/core/ErrorHandler.java

@@ -129,6 +129,7 @@ public class ErrorHandler extends Handler {
         startsWith.add("Failed to save player data for ");
         startsWith.add("Failed to check session lock for world located at");
         startsWith.add("Saving oversized chunk ");
+        startsWith.add("Ignoring plugin channel in incoming");
         ignoreStartsWith = Collections.unmodifiableList(startsWith);
 
         List<String> contains = new ArrayList<>();