File configuration.test.ts

tests/unit/back/configuration.test.ts:None–None

import { ScreenshotPreviewMode } from '@shared/BrowsePageLayout';
import { AppConfigData } from '@shared/config/interfaces';
import { getDefaultConfigData, overwriteConfigData } from '@shared/config/util';
import { defaultPreferencesData, overwritePreferenceData } from '@shared/preferences/util';