Add github actions and remove travis

.github/workflows/ruby.yml

@@ -0,0 +1,23 @@
+name: Ruby CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby-version: [ 3.0, 3.2, head, jruby, truffleruby ]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Ruby ${{ matrix.ruby-version }}
+        uses: ruby/setup-ruby@ec02537da5712d66d4d50a0f33b7eb52773b5ed1
+        with:
+          bundler-cache: true
+          ruby-version: ${{ matrix.ruby-version }}
+      - run: bundle install
+      - run: bundle exec rake