ci, img push: push images to github registry

Signed-off-by: Miguel Duarte Barroso <[email protected]>

.github/workflows/image-push.yaml

@@ -0,0 +1,34 @@
+name: Push container image
+on: 
+  push:
+    branches:
+      - master
+env:
+  image-push-owner: 'maiqueb'
+jobs:
+  push-amd64:
+    name: Image push/amd64
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Login to Container Registry
+        if: github.repository_owner == 'maiqueb'
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Push container image
+        if: github.repository_owner == 'maiqueb'
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          push: true
+          tags: ghcr.io/${{ github.repository }}:latest-amd64
+          file: images/Dockerfile