Move from deprecated image labels to modern standard.

.github/workflows/build.yml

@@ -1,14 +1,13 @@
 name: Build
 
 on:
-    push:
-      branches:
-        - main
-      tags:
-        - v*.*.*
+  push:
+    branches:
+      - main
+    tags:
+      - v*.*.*
 
 jobs:
-
   build:
     name: Build docker images.
     runs-on: ubuntu-latest
@@ -20,30 +19,30 @@ jobs:
     steps:
       - name: Checkout repository.
         uses: actions/checkout@v2
-        
+
       - name: Get version from tag.
         uses: little-core-labs/get-git-tag@v3.0.2
 
       - name: Get build date/time.
         id: date
-        run: echo "::set-output name=date::$(date --rfc-3339=seconds)"
+        run: echo "::set-output name=date::$(date -u --rfc-3339=seconds)"
 
       - name: Set up QEMU.
         id: qemu
         uses: docker/setup-qemu-action@v1
         with:
           platforms: arm64
-        
+
       - name: Set up Docker Buildx.
         uses: docker/setup-buildx-action@v1
-        
+
       - name: Login to GHCR.
         uses: docker/login-action@v1
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
-        
+
       - name: Login to DockerHub.
         uses: docker/login-action@v1
         with:
@@ -55,6 +54,6 @@ jobs:
         with:
           files: "docker-bake.hcl"
         env:
-            VCS_REF: ${{ github.sha }}
-            VERSION: ${{ env.GITHUB_TAG_NAME }}
-            BUILD_DATE: ${{ steps.date.outputs.date }}
+          VCS_REF: ${{ github.sha }}
+          VERSION: ${{ env.GIT_TAG_NAME }}
+          BUILD_DATE: ${{ steps.date.outputs.date }}