Liquid CanTrack tag (OSOE-644)

[Piedone]

If you want to conditionally do something in Liquid that depends on the user having given consent to tracking, you can't really do that, since you can't access ITrackingConsentFeature. So, let's add a Liquid tag that provides this information as a bool that you can use in ifs. Essentially, we want to be able to do the equivalent of this in Liquid:

var trackingConsentFeature = _hca.HttpContext.Features.Get<ITrackingConsentFeature>();

if (trackingConsentFeature is null || trackingConsentFeature.CanTrack)
{
     // Only insert the tracking script here.
}

This would be useful for including custom analytics scripts in DotNest Media Themes (though for DotNest OrchardCMS/OrchardCore#13825 would work too).

Jira issue