Removed leftover folder

openbb_sdk/sdk/core/openbb_core/app/model/abstract/singleton.py

@@ -1,15 +0,0 @@
-from typing import Dict, Generic, TypeVar
-
-T = TypeVar("T")
-
-
-class SingletonMeta(type, Generic[T]):
-    # TODO : check if we want to update this to be thread safe
-    _instances: Dict[T, T] = {}
-
-    def __call__(cls, *args, **kwargs):
-        if cls not in cls._instances:
-            instance = super().__call__(*args, **kwargs)
-            cls._instances[cls] = instance
-
-        return cls._instances[cls]