ast: fix pylance's type inference on Value._rhs_signals(). NFC

whitequark · whitequark · commit 57933b974d7e · 2023-09-25T14:15:11.000Z
diff --git a/amaranth/hdl/ast.py b/amaranth/hdl/ast.py
@@ -604,7 +604,7 @@ def _lhs_signals(self):
 
     @abstractmethod
     def _rhs_signals(self):
-        pass # :nocov:
+        raise NotImplementedError # :nocov:
 
 
 @final
