add run as root check

opensearch-1.x-node-installer.sh

@@ -73,6 +73,12 @@ while [ $secs -gt 0 ]; do
 done
 }
 
+#Check if user is root
+if ! [ "$(id -u)" = 0 ]; then
+   echo "You need to be root or have sudo privileges!"
+   exit 0
+fi
+
 # Test RAM size (4GB min) + CPUs (min 2)
 #Check system resources
 printf "\n\nVerifying System Resources:"