fix: image cache not working as expected

[imLinguin]

I've seen unnecessary requests to CDNs, I have since discovered our implementation of a cache was wrong fundamentally.

Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)