github: run CI nightly to test and ensure cache is up to date

Author: ahayzen-kdab

.github/workflows/github-cxx-qt-tests.yml

@@ -5,7 +5,13 @@
 # SPDX-License-Identifier: MIT OR Apache-2.0
 
 name: cxx-qt tests
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    # Run daily at 01:01
+    # This ensures CI still works and ensures the cache remains active
+    - cron: "1 1 * * *"
 # Cancel any previous runs for the same pull request
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}