Fix error when loading proficiencies from save

[Qrox]

Summary

SUMMARY: Bugfixes "Fix error when loading proficiencies from save"

Purpose of change

Looks like #42476 updated how proficiencies are saved but didn't actually update the save version when merged (perhaps some other PR also changed the save version to 31, which the merge tool thinks can just be merged safely but actually cannot be), so saves created in version 31 saved proficiencies as an array but the code tries to read an object for version > 30.

Describe the solution

Since both an array and an object can be saved in version 31 saves, we can only read according to whether the saved proficiencies are an array or object now.

Testing

Save now loads.

Additional context

We might want to find a way to avoid this kind of merge error.

[anothersimulacrum]

Thanks for getting this.
It looks like #42277 also adjusted the version, and the merge tools didn't mark that as a conflict.