Migrate testing to GH Actions from Travis

.github/workflows/testing.yml

@@ -0,0 +1,47 @@
+# This workflow uses actions that are not certified by GitHub.
+# They are provided by a third-party and are governed by
+# separate terms of service, privacy policy, and support
+# documentation.
+# This workflow will download a prebuilt Ruby version, install dependencies and run tests with Rake
+# For more information see: https://github.com/marketplace/actions/setup-ruby-jruby-and-truffleruby
+
+name: Testing
+
+on:
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  rubocop:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby-version:
+          - '2.5.8'
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby-version }}
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - name: Run Rubocop
+      run: bundle exec rake rubocop
+
+  spec_tests:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        ruby-version:
+          - '2.5.8'
+          - 'jruby-9.2.12.0'
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby-version }}
+        bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - name: Run spec tests
+      run: bundle exec rake test