[Wikipedia Loves Delpher Portrait gallery] Link to source image in Delpher from "Image provided by Delpher" tagline #54
Description
https://kbnlwikimedia.github.io/GLAMorousToHTML/extras/delpher_humans_q5_gallery.html --> bottom of each person card --> Image provided by Delpher.
When clicking on that text snippet, the user should be taken to the source of the image on Delpher.
If a card has more than one image, and thus a Swiper caroussel, the "Image provided by Delpher" should become part of the caroussel
To enable this functionality, the Delpher source URL should be extracted from the Wikitext of the corresponding page on Commons, and added to the structured data of the Commons-page.
See #55
From the SDoC, it can be requested in a structured way, and added into the Wikipedia Loves Delpher Portrait gallery.
