Update benchmark classification dataset (#4263)

* Rename dataset and update path for multiclass food classification

Author: eugene123tw

tests/perf_v2/tasks/classification.py

@@ -66,8 +66,8 @@
         extra_overrides={},
     ),
     DatasetInfo(
-        name="multiclass_food20_large",
-        path=Path("multiclass_classification/multilabel_food101_large"),
+        name="multiclass_food101_large",
+        path=Path("multiclass_classification/multiclass_food101_large"),
         group="large",
         extra_overrides={},
     ),