Add pil backend for vision transforms (#28035)

* add pil backend

Author: LielinJiang

python/paddle/tests/test_callbacks.py

@@ -105,7 +105,7 @@ def test_callback_verbose_2(self):
         self.run_callback()
 
     def test_visualdl_callback(self):
-        # visualdl not support python3
+        # visualdl not support python2
         if sys.version_info < (3, ):
             return