Update import statement in app.py

app.py

@@ -1,5 +1,5 @@
 # from evaluate.utils import launch_gradio_widget
-from tests import test_cases
+import tests
 from evaluate.utils.logging import get_logger
 from evaluate.utils import (
     infer_gradio_input_types,
@@ -64,4 +64,4 @@ def launch_gradio_widget(metric, test_cases):
 
 module = evaluate.load("danieldux/metric_template_1")
 
-launch_gradio_widget(module, [test_cases])
+launch_gradio_widget(module, tests)