Enable the sort-imports eslint rule (#1849)

## Description:

Enable the `sort-imports` eslint rule.

Fixes #1784

## 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

src/core/game/UnitGrid.ts

@@ -1,5 +1,5 @@
-import { PlayerID, Unit, UnitType } from "./Game";
 import { GameMap, TileRef } from "./GameMap";
+import { PlayerID, Unit, UnitType } from "./Game";
 import { UnitView } from "./GameView";
 
 export type UnitPredicate = (value: {