variables: lint fix

public/app/features/templating/specs/editor_ctrl.jest.ts

@@ -25,7 +25,7 @@ describe('VariableEditorCtrl', () => {
         },
       };
 
-      const ctrl = new VariableEditorCtrl(scope, {}, variableSrv, {});
+      return new VariableEditorCtrl(scope, {}, variableSrv, {});
     });
 
     it('should emit an error', () => {