You have created an interactive package for the installation hence you are getting the pop up
the following msi command line reference can only be used with SEP..
In section [UIRebootMode]
Valid values
0 - default will pop-up reboot with Y/N option if needs reboot
1 - display pop-up; do reboot when UI level is f,u or s
3 - no pop-up, no reboot when UI level is f,u,or s