fix: Fixed the `1st argument` name in classmethods (#31907)

Fixed the first argument name in few classmethods.

src/transformers/models/layoutlmv2/configuration_layoutlmv2.py

@@ -177,7 +177,7 @@ class LayoutLMv2Config(PretrainedConfig):
         )
 
     @classmethod
-    def get_default_detectron2_config(self):
+    def get_default_detectron2_config(cls):
         return {
             "MODEL.MASK_ON": True,
             "MODEL.PIXEL_STD": [57.375, 57.120, 58.395],

tests/optimization/test_optimization.py

@@ -209,5 +209,5 @@ class LambdaScheduleWrapper:
         return self.fn(*args, **kwargs)
 
     @classmethod
-    def wrap_scheduler(self, scheduler):
-        scheduler.lr_lambdas = list(map(self, scheduler.lr_lambdas))
+    def wrap_scheduler(cls, scheduler):
+        scheduler.lr_lambdas = list(map(cls, scheduler.lr_lambdas))