Prevent attempt to dereference None player in QuestAdvance.py.

git-svn-id: svn://svn.code.sf.net/p/crossfire/code/maps/trunk@21518 282e977c-c81d-0410-88c4-b93c2d0d6712

ChangeLog

@@ -1,5 +1,6 @@
 2020-10-20  Daniel Hawkins
 	* scorn/houses/tannery: Fix flagstone tile in entrance area that doesn't prevent casting.
+	* maps/python/quests/QuestAdvance.py: Bail when no player is provided. Avoids a core dump from the attempt to run the script in some scenarios.
 
 2020-10-12  Daniel Hawkins
 	* pup_land/begin/adv: Utilize the randomized item generation for the creator arch rather than separate

python/quests/QuestAdvance.py

@@ -47,6 +47,9 @@ def handle():
     if who.Level > skill.Level + 5:
       return
 
+  # If no player, return.
+  if player is None:
+    return
   # if a spell was used, then the killer is the spell object, find the owner
   if player.Type != Crossfire.Type.PLAYER:
     player = player.Owner