Move ci pipeline to github actions

.github/workflows/ci.yml

@@ -0,0 +1,35 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby-version: [ '3.0', '3.1', '3.2', '3.3', 'jruby-9.4' ]
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby-version }}
+          bundler-cache: true
+
+      - name: Update Bundler
+        run: gem install bundler
+
+      - name: Install dependencies
+        run: bundle install
+
+      - name: Run tests
+        run: bundle exec rspec

.tool-versions

@@ -0,0 +1 @@
+ruby 3.3.5

spec/lib/reverse_markdown_spec.rb

@@ -36,7 +36,8 @@
 
     describe 'force_encoding option', jruby: :exclude do
       it 'raises invalid byte sequence in UTF-8 exception' do
-        expect { ReverseMarkdown.convert("hi \255") }.to raise_error(Encoding::CompatibilityError)
+        # Older versions of ruby used to raise ArgumentError here. Remove when we drop support for 3.1.
+        expect { ReverseMarkdown.convert("hi \255") }.to raise_error { [Encoding::CompatibilityError, ArgumentError].include?(_1.class) }
       end
 
       it 'handles invalid byte sequence if option is set' do