Add support for nested images to LLava and VipLLava (#35558)

* move make_flat_list_of_images and make_batched_videos to image_utils

* remove unnecessary is_vision_available

* move make_nested_list_of_images to image_utils

* fix fast pixtral image processor

* fix import mllama

* fix make_nested_list_of_images

* add tests

* convert 4d arrays/tensors to list

* add test_make_batched_videos

* add support nested batch of videos

* fix image processing qwen2vl

tests/models/colpali/test_modeling_colpali.py

@@ -26,7 +26,6 @@ from tests.test_configuration_common import ConfigTester
 from tests.test_modeling_common import ModelTesterMixin, floats_tensor, ids_tensor
 from transformers import (
     is_torch_available,
-    is_vision_available,
 )
 from transformers.models.colpali.configuration_colpali import ColPaliConfig
 from transformers.models.colpali.modeling_colpali import ColPaliForRetrieval, ColPaliForRetrievalOutput
@@ -43,9 +42,6 @@ from transformers.testing_utils import (
 if is_torch_available():
     import torch
 
-if is_vision_available():
-    pass
-
 
 class ColPaliForRetrievalModelTester:
     def __init__(