fix(stark-ui): remove KeybordEvent.char

KeybordEvent.char is deprecated and will be remove from typesscript. To prepare the update to
angular 13 we need to remveoved occureneces

ISSUES CLOSED: NationalBankBelgium#3634

packages/stark-ui/src/modules/restrict-input-directive/directives/restrict-input.directive.ts

@@ -25,12 +25,13 @@ export class StarkRestrictInputDirective implements OnInit {
 	 */
 	@HostListener("keypress", ["$event"])
 	public eventHandler(event: KeyboardEvent): boolean {
-		// some browsers return the special key value (i.e. keys in the numeric keypad), in such cases we use the 'char'
-		// see: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key/Key_Values
-		/* tslint:disable-next-line:deprecation */
-		const key: string = event.key.length > 1 ? event.char : event.key;
-
-		return this.testValue(event, key);
+		// If event.key.length > 1 this means that a non char key was press ie: "Home" or "left"
+		// we let the default behaviour to those key works and just return `true`
+		if(event.key.length > 1) {
+			return true;
+		}
+		// if normal char we test the value
+		return this.testValue(event, event.key);
 	}
 
 	/**