MultiServer: update InvalidPacket text for location scouts (ArchipelagoMW#4485)

Author: Berserker66

MultiServer.py

@@ -1888,7 +1888,8 @@ async def process_client_cmd(ctx: Context, client: Client, args: dict):
             for location in args["locations"]:
                 if type(location) is not int:
                     await ctx.send_msgs(client,
-                                        [{'cmd': 'InvalidPacket', "type": "arguments", "text": 'LocationScouts',
+                                        [{'cmd': 'InvalidPacket', "type": "arguments",
+                                          "text": 'Locations has to be a list of integers',
                                           "original_cmd": cmd}])
                     return