Resolve spotbugs error

Author: yashpal2104

src/main/java/jenkins/advancedqueue/sorter/SorterStrategy.java

@@ -24,6 +24,7 @@
 package jenkins.advancedqueue.sorter;
 
 import edu.umd.cs.findbugs.annotations.CheckForNull;
+import edu.umd.cs.findbugs.annotations.CheckReturnValue;
 import edu.umd.cs.findbugs.annotations.NonNull;
 import hudson.ExtensionList;
 import hudson.ExtensionPoint;
@@ -66,6 +67,7 @@ public void onStartedItem(@NonNull LeftItem item, float weight) {}
     /**
      * Called when a {@link hudson.model.Item} leaves the queue and it is canceled.
      */
+    @CheckReturnValue
     public void onCanceledItem(@NonNull LeftItem item) {
         if (item.isCancelled()) {
             ExtensionList<SorterStrategy> all = all();