Bump action versions

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

.github/workflows/publish-image.yaml

@@ -22,7 +22,7 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
       - name: Build and push container image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           push: true
           tags: ghcr.io/${{ github.repository }}:latest