chore: test on ruby 3.3 and run tests on a schedule

.github/workflows/test.yml

@@ -1,18 +1,22 @@
 name: Tests
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: '0 0 1 * *'
 jobs:
   test:
     strategy:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
         # Due to https://github.com/actions/runner/issues/849, we have to use quotes for '3.0'
-        ruby: ['3.0', 3.1, 3.2, head, truffleruby]
+        ruby: ['3.0', 3.1, 3.2, 3.3, head, truffleruby]
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically
-    - run: bundle exec rspec
+    - run: bundle exec rspec