[CodeStyle] remove tabs in python fluid unittests (#46357)

python/paddle/fluid/tests/unittests/test_generate_proposal_labels_op.py

@@ -231,7 +231,7 @@ def _box_to_delta(ex_boxes, gt_boxes, weights):
 def _expand_bbox_targets(bbox_targets_input, class_nums, is_cls_agnostic):
     class_labels = bbox_targets_input[:, 0]
     fg_inds = np.where(class_labels > 0)[0]
-    #if is_cls_agnostic:
+    # if is_cls_agnostic:
     #     class_labels = [1 if ll > 0 else 0 for ll in class_labels]
     #     class_labels = np.array(class_labels, dtype=np.int32)
     #     class_nums = 2