Fix crash during intermission in Scientist 2023

See https://www.doomworld.com/forum/post/2870361.

src/wi_stuff.c

@@ -1028,7 +1028,7 @@ static void WI_DrawShowNextLoc(void)
         return;
 
     // draws which level you are entering...
-    if (gamemode != commercial || wbs->next != 30)
+    if (entering && (gamemode != commercial || wbs->next != 30))
         WI_DrawEL();
 }