fix(typehint): update type hint for class instance

Update egraph.py

ibis/common/egraph.py

@@ -4,7 +4,6 @@
 import itertools
 import math
 from typing import (
-    TYPE_CHECKING,
     Any,
     Hashable,
     Iterable,
@@ -17,9 +16,6 @@
 from ibis.common.graph import Node
 from ibis.util import promote_list
 
-if TYPE_CHECKING:
-    from typing_extensions import Self
-
 K = TypeVar("K", bound=Hashable)
 
 
@@ -108,7 +104,7 @@ def __len__(self) -> int:
         """Get the number of ids in the disjoint set."""
         return len(self._parents)
 
-    def __eq__(self, other: Self[K]) -> bool:
+    def __eq__(self, other: object) -> bool:
         """Check if the disjoint set is equal to another disjoint set.
 
         Parameters