yubioath-desktop: prefix QML2_IMPORT_PATH

[flokli]

Otherwise, yubioath-desktop can't find pyothersides qml files:

QQmlApplicationEngine failed to load component
qrc:/qml/main.qml:168 Type YubiKey unavailable
qrc:/qml/YubiKey.qml:2 module "io.thp.pyotherside" is not installed

[1] 17017 segmentation fault result/bin/yubioath-desktop

Motivation for this change

I wasn't able to run yubioath-desktop.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Assured whether relevant documentation is up to date
• Fits CONTRIBUTING.md.

---

[flokli]

@samueldr , @ttuegel: If I got it right, qml file loading seems to be adressed in #54525 as well, but not in #44047, right?

[Mic92]

Was this also a problem, when you install the application in your profile?

[flokli]

@Mic92 no, that only happened when building separately via nix-build, and then calling from the nix store. Still, I often use that to try out applications.

Could you backport this to 19.03 and 18.09 too?

[flokli]

backported to 19.03 in 5087648.

18.09 is still on 3.1.0, which seems to be much older (more Python and less QT, not using pyotherside at all) - so it's not affected.