Fix NDBranch typing.

Author: RaoulSchaffranek

src/pyk/kcfg/kcfg.py

@@ -325,7 +325,7 @@ def replace_target(self, node: KCFG.Node) -> KCFG.NDBranch:
     _edges: dict[int, Edge]
     _covers: dict[int, Cover]
     _splits: dict[int, Split]
-    _ndbranches: dict[int, NDBranch]
+    _ndbranches: dict[int, KCFG.NDBranch]
     _vacuous: set[int]
     _stuck: set[int]
     _aliases: dict[str, int]
@@ -827,7 +827,9 @@ def create_split(self, source_id: NodeIdLike, splits: Iterable[tuple[NodeIdLike,
         self.add_successor(split)
         return split
 
-    def ndbranches(self, *, source_id: NodeIdLike | None = None, target_id: NodeIdLike | None = None) -> list[NDBranch]:
+    def ndbranches(
+        self, *, source_id: NodeIdLike | None = None, target_id: NodeIdLike | None = None
+    ) -> list[KCFG.NDBranch]:
         source_id = self._resolve(source_id) if source_id is not None else None
         target_id = self._resolve(target_id) if target_id is not None else None
         return [
@@ -836,7 +838,7 @@ def ndbranches(self, *, source_id: NodeIdLike | None = None, target_id: NodeIdLi
             if (source_id is None or source_id == b.source.id) and (target_id is None or target_id in b.target_ids)
         ]
 
-    def contains_ndbranch(self, ndbranch: NDBranch) -> bool:
+    def contains_ndbranch(self, ndbranch: KCFG.NDBranch) -> bool:
         return ndbranch in self._ndbranches
 
     def create_ndbranch(