Support Google's CCPA framework

[benlk]

General note: https://privacy.google.com/businesses/rdp/

Specific implementation details: https://support.google.com/admanager/answer/9598414

This passes a configuration item to the GPT tag, which is mostly created and handled by jquery.dfp.js, which is drawn from the dfoPoptions object in

doubleclick-for-wp/js/vendor/jquery.dfp.js/jquery.dfp.js

Lines 243 to 246 in f106d47

	// Push DFP config options
	googletag.cmd.push(function () {
	var pubadsService = googletag.pubads();

We may need to patch jQuery.dfp.js to support this, though, since jQuery.dfp.js hasn't received a tagged release since 2016: https://github.com/coop182/jquery.dfp.js/releases

There's a slightly-updated downstream version at maxx0r/jquery.dfp.js@1fbab93

• figure out how to add the config item to dfp
• add the configuration item to dfp
• add a checkbox in the plugin settings
• admonish site admins to mention ads in their https://wordpress.org/support/article/settings-privacy-screen/