The Video Image Screen URL Returns a "NoSuchKey" Error

Hey there, I noticed an issue with some recent videos where fetching the `screen_url` image returns an XML structure with a "NoSuchKey" error. For example, the screen_url for Crime Crew Episode 10:

https://www.giantbomb.com/api/image/screen_medium/3115603-cp_gtaonline_heist05_part01_fine.00_01_53_41.still001.jpg

I'm going to update my app to pick the next best image if the screen URL doesn't exist, but this is tricky when the API response includes a valid screen URL as opposed to `null`.

This issue seems to be back. It's inconsistent, though; Best of Giant Bomb 177,Quick Look: Yooka-Laylee and the Impossible Lair and Quick Look: Later Alligator are all affected, but other videos seem fine.