fix: configure luxon

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

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
+  }
+}