TEST: Add GH workflow

.github/workflows/build-ruby.yml

@@ -0,0 +1,87 @@
+name: Build Ruby
+
+on:
+  push:
+    branches:
+      - "**"
+
+env:
+  REGISTRY: ghcr.io
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - engine: ruby
+            version: 2.1.10
+            dockerfile: Dockerfile-2.1.10
+          - engine: ruby
+            version: 2.2.10
+            dockerfile: Dockerfile-2.2.10
+          - engine: ruby
+            version: 2.3.8
+            dockerfile: Dockerfile-2.3.8
+          - engine: ruby
+            version: 2.4.10
+            dockerfile: Dockerfile-2.4.10
+          - engine: ruby
+            version: 2.5.9
+            dockerfile: Dockerfile-2.5.9
+          - engine: ruby
+            version: 2.6.7
+            dockerfile: Dockerfile-2.6.7
+          - engine: ruby
+            version: 2.7.3
+            dockerfile: Dockerfile-2.7.3
+          - engine: ruby
+            version: 3.0.3
+            dockerfile: Dockerfile-3.0.3
+          - engine: ruby
+            version: 3.1.1
+            dockerfile: Dockerfile-3.1.1
+          - engine: ruby
+            version: 3.2.0-preview2
+            dockerfile: Dockerfile-3.2.0-preview2
+          - engine: jruby
+            version: 9.2.18.0
+            dockerfile: Dockerfile-jruby-9.2-latest
+          - engine: jruby
+            version: 9.2.8.0
+            dockerfile: Dockerfile-jruby-9.2.8.0
+          - engine: jruby
+            version: 9.3.4.0
+            dockerfile: Dockerfile-jruby-9.3-latest
+          - engine: truffleruby
+            version: 22.3.0
+            dockerfile: Dockerfile-truffleruby-22.3.0
+    runs-on: ubuntu-latest
+    name: Build (${{ matrix.engine }} ${{ matrix.version }})
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Build image (x86_64)
+        run: |
+          docker buildx build . --cache-from=type=gha --cache-to=type=gha,mode=max --platform linux/x86_64 -f ${{ matrix.dockerfile }} --tag ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb
+        working-directory: .circleci/images/primary
+      - name: Test image (x86_64)
+        run: |
+          docker run --platform linux/x86_64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb ruby -e 'puts RUBY_DESCRIPTION'
+          docker run --platform linux/x86_64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb gem --version
+          docker run --platform linux/x86_64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb bundle --version
+      - name: Enable aarch64 emulation (x86_64)
+        run: |
+          docker run --privileged --rm tonistiigi/binfmt --install arm64
+      - name: Build image (aarch64)
+        run: |
+          docker buildx build . --cache-from=type=gha --cache-to=type=gha,mode=max --platform linux/aarch64 -f ${{ matrix.dockerfile }} --tag ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb
+        working-directory: .circleci/images/primary
+      - name: Test image (aarch64)
+        run: |
+          docker run --platform linux/aarch64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb ruby -e 'puts RUBY_DESCRIPTION'
+          docker run --platform linux/aarch64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb gem --version
+          docker run --platform linux/aarch64 --rm ${{ env.REGISTRY }}/datadog/dd-trace-rb/${{ matrix.engine }}:${{ matrix.version }}-dd-trace-rb bundle --version
+      - name: Log in to the Container Registry
+        run: |
+          echo ${{ secrets.GITHUB_TOKEN }} | docker login ${{ env.REGISTRY }} -u ${{ github.actor }} --password-stdin