Safetycases.ui: Avoid warning and ref corresponding TODO.

* [YELLOW]
refs 3296

org.fortiss.af3.safetycases.ui/trunk/src/org/fortiss/af3/safetycases/ui/commands/ShowActualChangeImpact.java

@@ -64,6 +64,8 @@ public class ShowActualChangeImpact implements IContextMenuContributor {
 	private class ShowActualChangeImpactAction extends Action {
 
 		/** The selected argument element. */
+		// TODO: #3296
+		@SuppressWarnings("unused")
 		private ArgumentElement selectedArgumentElement;
 
 		/** Constructor. */