Update Doorstop config to target preloader dll

doorstop/doorstop_config.ini

@@ -2,4 +2,4 @@
 # Specifies whether assembly executing is enabled
 enabled=true
 # Specifies the path (absolute, or relative to the game's exe) to the DLL/EXE that should be executed by Doorstop
-targetAssembly=BepInEx\core\BepInEx.dll
+targetAssembly=BepInEx\core\BepInEx.Preloader.dll