Add a hard timeout on "docker pull" in hello-world/update.sh

hello-world/update.sh

@@ -3,8 +3,8 @@ set -Eeuo pipefail
 
 image="${1:-hello-world}"
 
-docker pull hello-world &> /dev/null || exit 0
-docker pull "$image" &> /dev/null || exit 0
+timeout 5s docker pull hello-world &> /dev/null || exit 0
+timeout 5s docker pull "$image" &> /dev/null || exit 0
 
 exec > "$(dirname "$(readlink -f "$BASH_SOURCE")")/content.md"