fix: ensure proper newline at end of file in test files

Author: shunk031

tests/modules/rankers/layout_prompter_test.py

@@ -184,4 +184,4 @@ def test_all_empty_layouts(self):
 
         # All inputs have empty layouts, should raise ValueError
         with pytest.raises(ValueError):
-            ranker.invoke([empty_data1, empty_data2])
+            ranker.invoke([empty_data1, empty_data2])

tests/modules/selectors/content_aware_selector_test.py

@@ -84,4 +84,4 @@ def test_content_aware_selector(
         selector = ContentAwareSelector(examples=candidate_examples)
         selector_output = selector.select_examples(processed_test_data)
 
-        assert len(selector_output.selected_examples) == num_prompt
+        assert len(selector_output.selected_examples) == num_prompt

tests/modules/serializers/content_aware_serializer_test.py

@@ -102,4 +102,4 @@ def test_content_aware_serializer(
             },
         )
         for message in prompt.to_messages():
-            message.pretty_print()
+            message.pretty_print()