Update code-server.sh

fixes https://github.com/tteck/Proxmox/issues/2608

misc/code-server.sh

@@ -47,6 +47,7 @@ function error_exit() {
 clear
 header_info
 if command -v pveversion >/dev/null 2>&1; then echo -e "⚠️  Can't Install on Proxmox "; exit; fi
+if [ -e /etc/alpine-release ]; then echo -e "⚠️  Can't Install on Alpine"; exit; fi
 while true; do
     read -p "This will Install ${APP} on $hostname. Proceed(y/n)?" yn
     case $yn in