only check valueMissing if required

Author: nielslyngsoe

src/Umbraco.Web.UI.Client/src/packages/media/media/components/input-image-cropper/input-image-cropper.element.ts

@@ -60,7 +60,7 @@ export class UmbInputImageCropperElement extends UmbFormControlMixin<
 			'valueMissing',
 			() => this.requiredMessage ?? UMB_VALIDATION_EMPTY_LOCALIZATION_KEY,
 			() => {
-				return !this.value || (this.value.src === '' && this.value.temporaryFileId == null);
+				return !!this.required && (!this.value || (this.value.src === '' && this.value.temporaryFileId == null));
 			},
 		);
 	}