[tests] expand flex-attn test for vision models (#38434)

* expand the test for VLMs

* typo

* mark models `supports_flex` + expand test for additional kwargs

* flex attn for refactored vision models

* fix copies

* fix

* unskip

* style

* address comments

tests/models/got_ocr2/test_modeling_got_ocr2.py

@@ -236,10 +236,6 @@ class GotOcr2ModelTest(ModelTesterMixin, GenerationTesterMixin, PipelineTesterMi
     def test_past_key_values_format(self):
         pass
 
-    @unittest.skip(reason="Vision backbone doesn't support FLEX yet!")
-    def test_flex_attention_with_grads(self):
-        pass
-
 
 @require_torch
 class GotOcr2IntegrationTest(unittest.TestCase):