Add GitHub Container Registry login step

.github/workflows/docker-image.yml

@@ -14,6 +14,12 @@ jobs:
     - uses: actions/checkout@v4
     - name: Set environment variable
       run: echo "VERSION=$(date +%s)" >> $GITHUB_ENV
+    - name: 'Login to GitHub Container Registry'
+      uses: docker/login-action@v1
+      with:
+        registry: ghcr.io
+        username: ${{github.actor}}
+        password: ${{secrets.GITHUB_TOKEN}}
     - name: Build the Docker image
       run: docker build . --file Dockerfile --tag ghcr.io/raspberryprogramming/tc2-bbs-mesh:$VERSION
     - name: Add latest tag to docker image