Fix scale control default parameters (maplibre#4002)

Before this CL, the following would generate an error:

```ts
const scaleCtrl = new ScaleControl():
```

because options is not marked as optional.

Co-authored-by: Harel M <[email protected]>

CHANGELOG.md

@@ -6,8 +6,10 @@
 ### 🐞 Bug fixes
 - Fix different unwanted panning changes at the end of a panning motion, that happen on a large screen ([#3935](https://github.com/maplibre/maplibre-gl-js/issues/3935))
 - Fix image sources not being marked as loaded on error
+- Fix ScaleControl options should be optional. ([#4002](https://github.com/maplibre/maplibre-gl-js/pull/4002))
 - Fix race condition in SourceCache that makes unit tests unstable. Eliminate a redundant 'visibility' event fired from Style class. ([#3992](https://github.com/maplibre/maplibre-gl-js/issues/3992))
 
+
 ## 4.1.2
 
 ### ✨ Features and improvements

src/ui/control/scale_control.ts

@@ -1,5 +1,4 @@
 import {DOM} from '../../util/dom';
-import {extend} from '../../util/util';
 
 import type {Map} from '../map';
 import type {ControlPosition, IControl} from './control';
@@ -51,8 +50,8 @@ export class ScaleControl implements IControl {
     _container: HTMLElement;
     options: ScaleControlOptions;
 
-    constructor(options: ScaleControlOptions) {
-        this.options = extend({}, defaultOptions, options);
+    constructor(options?: ScaleControlOptions) {
+        this.options = {...defaultOptions, ...options};
     }
 
     getDefaultPosition(): ControlPosition {