Adding 'should authenticate reboot="true"' to a installer's distribution file.

gistfile1.xml

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<installer-script authoringTool="Packages" authoringToolVersion="1.1.2" authoringToolBuild="2B89" minSpecVersion="1.0">
    <options should-authenticate-reboot="true"/>
    <!--+==========================+
        |       Presentation       |
        +==========================+-->
    <title>DISTRIBUTION_TITLE</title>
    <!--+==========================+
        |         Installer        |
        +==========================+-->
    <choices-outline>
        <line choice="installer_choice_1"/>
    </choices-outline>
    <choice id="installer_choice_1" title="Reboot and Bypass Login Windows" description="">
        <pkg-ref id="com.company.pkg.RebootandBypassLoginWindows"/>
    </choice>
    <!--+==========================+
        |    Package References    |
        +==========================+-->
    <pkg-ref id="com.company.pkg.RebootandBypassLoginWindows" version="1.0" auth="Root" installKBytes="0" onConclusion="RequireRestart">#Reboot_and_Bypass_Login_Windows.pkg</pkg-ref>
    <!--+==========================+
        |    JavaScript Scripts    |
        +==========================+-->
</installer-script>