fixed lazy logging

Author: vlad-karp

src/maxtext/trainers/post_train/distillation/train_distill.py

@@ -228,7 +228,7 @@ def wrt_filter(path, x):
         if not isinstance(x, base_wrt):
           return False
         freeze = student_freeze_param_filter(path)
-        logging.info(f"Student model freezing info: Parameter {path}; freeze={freeze}")
+        logging.info("Student model freezing info: Parameter %s; freeze=%s", path, freeze)
         return not freeze
 
       self.wrt_filter = wrt_filter