use GitHub actions bulid/push image (#44)

build and push image tag latest-*.* to docker hub

Author: bestlong

.github/workflows/dockerimage.yml

@@ -0,0 +1,33 @@
+name: Docker Image CI
+
+on:
+  push:
+    branches: master
+  schedule:
+  - cron: 0 0 * * 6
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        php_version: [56, 70, 71, 72, 73, 74]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Build the Docker image
+      env:
+        PHP_VERSION: ${{ matrix.php_version }}
+      run: |
+        export TAG_VERSION=${PHP_VERSION:0:1}.${PHP_VERSION:1:1}
+        docker build . --file Dockerfile-${{ matrix.php_version }} --tag laradock/php-fpm:latest-${TAG_VERSION}      
+        docker image ls
+
+    - name: Push image to Docker hub
+      if: success()
+      env:
+        PHP_VERSION: ${{ matrix.php_version }}
+      run: |
+        export TAG_VERSION=${PHP_VERSION:0:1}.${PHP_VERSION:1:1}
+        echo ${{ secrets.DOCKER_HUB_PASSWORD }} | docker login -u ${{ secrets.DOCKER_HUB_USER }} --password-stdin
+        docker push laradock/php-fpm:latest-${TAG_VERSION}
+        docker logout