.github/workflows/ubuntu.yml in textbringer-1.3.0 vs .github/workflows/ubuntu.yml in textbringer-1.4.1

@@ -2,22 +2,23 @@
 
 on: [push]
 
 jobs:
   test:
+    runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: [ head, 3.1, 3.0, 2.7 ]
-    runs-on: ubuntu-latest
+        ruby: [ head, 3.3, 3.2, 3.1 ]
     timeout-minutes: 10
+    env:
+      RUBYOPT: --enable-frozen-string-literal --debug-frozen-string-literal
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
     - name: Install dependencies
       run: |
         sudo apt install libncursesw5-dev
-        gem install bundler --no-document
         bundle install
     - name: Run test
       run: xvfb-run bundle exec rake test