How do I create a thank you landing page so that all a newsletter subscriber has to do is click the link in my newsletter (which will automatically tag them) and they get to the thank you page. So I don't want to send them to another email subscription page, I want them to be able to "click here to opt in to the waitlist" type of thing, since they're already subscribers. Is that possible without creating an external landing page/thank you page? It seems like all of ConvertKit's landing pages require an email input?