Clarify error message and remove PIL import.

annotator/mediapipe_face/__init__.py

@@ -1,5 +1,3 @@
-from PIL import Image
-
 from .mediapipe_face_common import generate_annotation
 
 

annotator/mediapipe_face/mediapipe_face_common.py

@@ -106,7 +106,7 @@ def generate_annotation(
         results = facemesh.process(img_rgb).multi_face_landmarks
 
         if results is None:
-            print("Results is None rather than empty.  There may have been an exception in processing.")
+            print("No faces detected in controlnet image for Mediapipe face annotator.")
             return numpy.zeros_like(img_rgb)
 
         # Filter faces that are too small