test/owtestlearners: Cleanup after test

Author: ales-erjavec

Orange/widgets/evaluate/tests/test_owtestlearners.py

@@ -26,6 +26,11 @@ def setUp(self):
         super().setUp()
         self.widget = self.create_widget(OWTestLearners)  # type: OWTestLearners
 
+    def tearDown(self):
+        self.widget.onDeleteWidget()
+        super().tearDown()
+
+
     def test_basic(self):
         data = Table("iris")[::3]
         self.send_signal(self.widget.Inputs.train_data, data)