Collections page looks strange when collection not found

[Irakli Mchedlishvili]

If you try and visit collections (awesome) page that not exists it displays a broken image and 404 not found text Eg: https://datahub.io/collections/linking-open-data

How to reproduce

• go to https://datahub.io/collections/linking-open-data
• take a look at image icon
• take a look at the text "404: Not Found"

Expected behavior

• Displays nice image or not at all
• there's no plain text of "404: Not Found"