Drop TravisCI, start using GitHub Actions CI

Author: etagwerker

.github/actions/ci.yml

@@ -0,0 +1,28 @@
+name: Ruby CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    name: Ruby gem CI
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby: ['2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2']
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby }}
+    - name: Install dependencies
+      run: |
+        gem install bundler
+        bundle install --jobs 4 --retry 3
+    - name: Run tests
+      run: bundle exec rake
+