[mob][photos] Fix empty facethumbnail due to decoding issue

mobile/lib/utils/face/face_box_crop.dart

@@ -216,7 +216,7 @@ Future<Map<String, Uint8List>?> _getFaceCrops(
     faceBoxes,
   );
   final Map<String, Uint8List> result = {};
-  for (int i = 0; i < faceIds.length; i++) {
+  for (int i = 0; i < faceCrop.length; i++) {
     result[faceIds[i]] = faceCrop[i];
   }
   return result;

mobile/lib/utils/image_ml_util.dart

@@ -170,7 +170,7 @@ Future<List<Uint8List>> generateFaceThumbnailsUsingCanvas(
     return faceThumbnails;
   } catch (e, s) {
     _logger.severe(
-      'Error generating face thumbnails. cropImage problematic input argument: ${faceBoxes[i]}',
+      'Error generating face thumbnails. cropImage problematic input argument: ${i}th facebox: ${faceBoxes[i].toString()}',
       e,
       s,
     );