Add GitHub Actions workflow for Docker testing

Author: luandro

.github/workflows/docker-test.yml

@@ -0,0 +1,21 @@
+name: Docker Test
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+      
+      - name: Run Docker test script
+        run: |
+          chmod +x ./scripts/test-mapeo-config.sh
+          ./scripts/test-mapeo-config.sh