enable factories by default (#1718)

## Description:

Enable factories by default in singplayer private & public games.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I have read and accepted the CLA agreement (only required once).

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

src/server/MapPlaylist.ts

@@ -8,7 +8,6 @@ import {
   GameType,
   Quads,
   Trios,
-  UnitType,
 } from "../core/game/Game";
 import { PseudoRandom } from "../core/PseudoRandom";
 import { GameConfig, TeamCountConfig } from "../core/Schemas";
@@ -88,7 +87,7 @@ export class MapPlaylist {
       gameMode: mode,
       playerTeams,
       bots: 400,
-      disabledUnits: [UnitType.Train, UnitType.Factory],
+      disabledUnits: [],
     } satisfies GameConfig;
   }