fix: configure luxon

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

frontend/src/pages/_app.tsx

@@ -13,10 +13,13 @@ import { BaseHead } from '../components/layout/base-head'
 import { UiNotificationBoundary } from '../components/notifications/ui-notification-boundary'
 import { StoreProvider } from '../redux/store-provider'
 import { BaseUrlFromEnvExtractor } from '../utils/base-url-from-env-extractor'
+import { configureLuxon } from '../utils/configure-luxon'
 import { ExpectedOriginBoundary } from '../utils/uri-origin-boundary'
 import type { AppInitialProps, AppProps } from 'next/app'
 import React from 'react'
 
+configureLuxon()
+
 interface AppPageProps {
   baseUrls: BaseUrls | undefined
 }

frontend/src/utils/configure-luxon.ts

@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { Settings } from 'luxon'
+
+export const configureLuxon = () => {
+  Settings.throwOnInvalid = true
+}
+
+declare module 'luxon' {
+  interface TSSettings {
+    throwOnInvalid: true
+  }
+}