Use GitHub actions to build Docker image

.github/workflows/image.yml

@@ -0,0 +1,19 @@
+name: Build stable multiarch image
+
+on:
+  push:
+    branches: master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout code
+        uses: actions/checkout@v2
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build image
+        run: bin/build

bin/build

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+#!/usr/bin/env sh
+
+LATEST_TAG="$(git describe --tags --abbrev=0)"
+WP_VERSION="${1:-$LATEST_TAG}"
+
+if [ -z "${WP_VERSION}" ]; then
+  echo "Error: WP_VERSION is null"
+  exit 1
+fi
+
+docker build --build-arg WP_VERSION=${WP_VERSION} --push --tag "nlss/wordpress:${WP_VERSION}" --tag "nlss/base-alpine:latest" .