Add a new recipe to Umami demo for homemade hummus

MR 3837 appears to address the "400g tin chickpeas in water" into spanish.

We need to update core/profiles/demo_umami/modules/demo_umami_content/default_content/LICENCE.txt with the appropriate license for the image. However, I'm not sure what's the process for that since based on the issue summary, I'm not certain if the author of the image has a Drupal.org account.

Addressed #52 feedback point. Tried to locate the (Anna Christoforou) author's Drupal org account, but not able to locate the user(Anna Christoforou). For consistency, follow the contents of the license text file and mention the user with the user's image.

Thanks very much @Rassoni

Discussed with @catch about this issue since it involves relicensing pictures from a person who is not involved on the issue. We agreed that to be able to proceed here, we need a written statement from the author of the picture/recipe that we can ship the picture under CC BY-SA 4.0.