nginx_build_script : add note regarding lua

nginx_build_script/README.md

@@ -8,6 +8,11 @@ curl https://raw.githubusercontent.com/minoplhy/scriptbox/main/nginx_build_scrip
 bash ~/nginx_scriptbox.sh
 ```
 
+#### Note :  don't forgot to add necessary `lua_package_path` directive to `nginx.conf`, in the http context. else Nginx won't run.
+```lua
+lua_package_path "/opt/nginx-lua-module/lib/lua/?.lua;;";
+```
+
 systemd Template:
 `Location : /lib/systemd/system/nginx.service`