Remove some pipeline skip cases (#22865)

fix
Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

tests/models/fnet/test_modeling_fnet.py

@@ -303,7 +303,7 @@ class FNetModelTest(ModelTesterMixin, PipelineTesterMixin, unittest.TestCase):
     def is_pipeline_test_to_skip(
         self, pipeline_test_casse_name, config_class, model_architecture, tokenizer_name, processor_name
     ):
-        if pipeline_test_casse_name == "QAPipelineTests":
+        if pipeline_test_casse_name == "QAPipelineTests" and not tokenizer_name.endswith("Fast"):
             return True
 
         return False

tests/models/mbart/test_modeling_mbart.py

@@ -257,8 +257,7 @@ class MBartModelTest(ModelTesterMixin, GenerationTesterMixin, PipelineTesterMixi
     def is_pipeline_test_to_skip(
         self, pipeline_test_casse_name, config_class, model_architecture, tokenizer_name, processor_name
     ):
-        if pipeline_test_casse_name != "FeatureExtractionPipelineTests":
-            # IndexError: index out of range in self
+        if pipeline_test_casse_name == "QAPipelineTests" and not tokenizer_name.endswith("Fast"):
             return True
 
         return False

tests/models/xlnet/test_modeling_xlnet.py

@@ -546,8 +546,10 @@ class XLNetModelTest(ModelTesterMixin, GenerationTesterMixin, PipelineTesterMixi
     def is_pipeline_test_to_skip(
         self, pipeline_test_casse_name, config_class, model_architecture, tokenizer_name, processor_name
     ):
-        # IndexError: index out of range in self
-        return True
+        if pipeline_test_casse_name == "QAPipelineTests" and not tokenizer_name.endswith("Fast"):
+            return True
+
+        return False
 
     # XLNet has 2 QA models -> need to manually set the correct labels for one of them here
     def _prepare_for_class(self, inputs_dict, model_class, return_labels=False):