Update docker-update.yml to use gcr.io

Instead of the deprecated github docker registry

.github/workflows/docker-update.yml

@@ -14,7 +14,10 @@ on:
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
 
-  # This workflow contains a single job which does both the building and the pushing
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
 jobs:
   push_to_registry:
     name: Push Docker image to GitHub Packages
@@ -25,12 +28,25 @@ jobs:
     steps:
       - name: Check out the repo
         uses: actions/checkout@v2
-      - name: Push to GitHub Packages
-        uses: docker/build-push-action@v1
+        
+      - name: Log in to the Container registry
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
+          registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
-          registry: docker.pkg.github.com
-          repository: mszep/pandoc_resume/resume_builder
-          tag_with_ref: true
-          dockerfile: .docker/resume.dockerfile
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+  
+      - name: Build and Push to GitHub Packages
+        uses: docker/build-push-action@ad44023a93711e3deb337508980b4b5e9bcdc5dc
+        with:
+          context: .docker/
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+