Tests: tag `test_save_load_fast_init_from_base` as flaky (#28930)

tests/test_modeling_common.py

@@ -64,6 +64,7 @@ from transformers.models.auto.modeling_auto import (
 )
 from transformers.testing_utils import (
     CaptureLogger,
+    is_flaky,
     is_pt_flax_cross_test,
     is_pt_tf_cross_test,
     require_accelerate,
@@ -381,6 +382,7 @@ class ModelTesterMixin:
                         m.gradient_checkpointing, f"Module {n} does not have gradient_checkpointing set to False"
                     )
 
+    @is_flaky(description="low likelihood of failure, reason not yet discovered")
     def test_save_load_fast_init_from_base(self):
         config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
         if config.__class__ not in MODEL_MAPPING: