Try amd64 only builds

.github/workflows/on-push-amd64-only.yml

@@ -0,0 +1,32 @@
+name: Build Docker image (amd64 only) on push
+
+on: push
+
+env:
+  DOCKER_CLI_EXPERIMENTAL: enabled
+
+jobs:
+  build:
+    name: Build Docker image
+    runs-on: ubuntu-18.04
+    steps:
+      - name: Checkout project
+        uses: actions/checkout@v2
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+        id: qemu
+
+      - name: Setup Docker buildx action
+        uses: docker/setup-buildx-action@v1
+        id: buildx
+
+      - name: Show available Docker buildx platforms
+        run: echo ${{ steps.buildx.outputs.platforms }}
+
+      - name: Run Docker buildx
+        run: |
+          docker buildx build \
+          --platform linux/amd64 \
+          --tag sensei \
+          .