Update hasse_diagram.py

voilà, voilà

Author: fchapoton

src/sage/combinat/posets/hasse_diagram.py

@@ -443,8 +443,7 @@ def bottom(self) -> int | None:
             next(min_elms)
         except StopIteration:
             return bottom
-        else:
-            return None
+        return None
 
     def has_bottom(self) -> bool:
         """
@@ -482,8 +481,7 @@ def top(self) -> int | None:
             next(max_elms)
         except StopIteration:
             return top
-        else:
-            return None
+        return None
 
     def has_top(self) -> bool:
         """