bug#43263: OBS icons are missing

[Leo Famulari]

The icons are missing from our package of OBS (Open Broadcaster
Software), making the program unusable.

This problem manifests both on Guix System and Guix on Debian, using a
recent revision of Guix [0].

I have the hicolor, adwaita, and breeze icon themes in my profile, but
it seems like they are not what OBS needs.

I've attached pictures to show how it should look, and how it does look.

[0] Guix Git commit edb994d3a85c0eaae3bd0d50aa575bcbbefe7c61

good.png
Description: PNG image

bad.png
Description: PNG image