Kanka-Foundry entries no longer work in GM Screen

[eXaminator]

Environment Details

• Foundry Core Version: 0.8.8

Describe the bug
I changed how the sheet class is selected for Kanka journal entries and this no longer works with how GM Screen works. This change on my end was made to be more future proof and hopefully improve the compatibility with other modules /systems (like PF2e) – I know, it's kind of ironic that this breaks compatibility in this case.

What I have changed is, that I use this shim by @zeel01: https://gist.github.com/zeel01/ffcbe77ad3e430fe44562e95a55d75e3

This adds the option to set sheets on a per document basis for journal entries, just as it is already possible for actors and items. This feature will probably (hopefully) also land as a core function in Foundry in the (near?) future. See the following issues in this regard:
https://gitlab.com/foundrynet/foundryvtt/-/issues/4994
https://gitlab.com/foundrynet/foundryvtt/-/issues/5298

This might have synergies with #95 as far as I can tell.

To Reproduce

• Sync a kanka entity
• Drag it to the GM screen
• It uses the default sheet

Expected behavior
It should use the Kanka-Foundry specific sheet