fix regression fixtures taclets.old.txt

Author: wadoon

key.core/src/test/resources/de/uka/ilkd/key/nparser/taclets.old.txt

@@ -17991,6 +17991,7 @@ tryCatchThrow {
     #slist1
   }
 ... }}| (post))
+\sameUpdateLevel
 \add []==>[equals(#se,null)] \replacewith(#allmodal ((modal operator))|{{ ..
   if (#se instanceof #t) {
     #t #v0;