Add FreeBSD to workflow.

.github/workflows/ruby.yml

@@ -15,15 +15,31 @@ jobs:
   test:
     strategy:
       matrix:
-        ruby-version: ['2.6', '2.7', '3.0', '3.1', '3.2', '3.3']
+        ruby-version: ['2.7', '3.0', '3.1', '3.2', '3.3']
         platform: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.platform }}
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Ruby
+    - name: Setup Ruby
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby-version }}
         bundler-cache: true
     - name: Run tests
       run: bundle exec rake
+  freebsd:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Test in FreeBSD
+      id: test
+      uses: vmactions/freebsd-vm@v1
+      with:
+        usesh: true
+        prepare: |
+          pkg install -y ruby devel/ruby-gems
+
+        run: |
+          gem install bundler --no-document
+          bundle install --quiet
+          bundle exec rspec