Update docker-php7.4.yml

.github/workflows/docker-php7.4.yml

@@ -0,0 +1,28 @@
+name: Build & Publish Docker Image PHP 7.4
+
+on:
+  push:
+    branches:
+      - php7.4
+  workflow_dispatch:
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set output
+        id: vars
+        run: echo ::set-output name=tag::$
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
+      - name: Build and push
+        id: docker_build
+        uses: docker/build-push-action@v2
+        with:
+          push: true
+          tags: diouxx/glpi:php7.4