Consolidate CI action

.github/workflows/ci.yml

@@ -0,0 +1,30 @@
+name: Unit Tests
+
+on: [push, pull_request]
+jobs:
+  build:
+    name: "Ruby: ${{ matrix.ruby }} OS: ${{ matrix.os }}"
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, windows-latest, ubuntu-latest]
+        ruby: ["2.3", "2.4", "2.5", "2.6", "2.7"]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+        with:
+          fetch-depth: 10
+      - name: Select Ruby Version
+        uses: eregon/use-ruby-action@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          base: update
+      - name: Update RubyGems & Bundler
+        run: gem update --system --no-document --conservative
+      - name: Install Dependencies
+        run: bundle install --jobs=3 --retry=3
+      - name: Run Test
+        run: ruby -v && bundle exec rake
+        env:
+          CI: true