Remove overload default values (#1557)

Author: cdce8p

astroid/nodes/node_ng.py

@@ -502,31 +502,31 @@ def set_local(self, name, stmt):
     def nodes_of_class(
         self,
         klass: type[_NodesT],
-        skip_klass: SkipKlassT = None,
+        skip_klass: SkipKlassT = ...,
     ) -> Iterator[_NodesT]:
         ...
 
     @overload
     def nodes_of_class(
         self,
         klass: tuple[type[_NodesT], type[_NodesT2]],
-        skip_klass: SkipKlassT = None,
+        skip_klass: SkipKlassT = ...,
     ) -> Iterator[_NodesT] | Iterator[_NodesT2]:
         ...
 
     @overload
     def nodes_of_class(
         self,
         klass: tuple[type[_NodesT], type[_NodesT2], type[_NodesT3]],
-        skip_klass: SkipKlassT = None,
+        skip_klass: SkipKlassT = ...,
     ) -> Iterator[_NodesT] | Iterator[_NodesT2] | Iterator[_NodesT3]:
         ...
 
     @overload
     def nodes_of_class(
         self,
         klass: tuple[type[_NodesT], ...],
-        skip_klass: SkipKlassT = None,
+        skip_klass: SkipKlassT = ...,
     ) -> Iterator[_NodesT]:
         ...