change test param

Author: felipe207

tests/langkit/metrics/test_topic.py

@@ -157,4 +157,4 @@ def test_custom_topic():
     assert actual.index.tolist() == expected_columns
     for column in expected_columns:
         if column not in ["prompt", "response"]:
-            assert actual.loc[column]["distribution/max"] >= 0.65
+            assert actual.loc[column]["distribution/max"] >= 0.50