Remove GConf module

[vially]

GConf used to be a dependency of Chromium until around version 66 (chromium#768027) and a dependency of Electron until version 7 (https://github.com/electron/electron/pull/19498).

I haven't actually checked this but it's possible that GConf was never a direct dependency of Electron, but rather a transitive dependency coming from Chromium. If that's the case, then it would mean that Electron 2 was the latest version that actually required GConf (because Electron 3 was based on Chromium 66 (source)).

So unless GConf is directly used by an app (which seems unlikely given that it's been deprecated for 8 years now), my impression is that not a lot of Electron apps actually need the GConf dependency. And the ones that do can still add it as a module to their manifest instead of inheriting it from org.electronjs.Electron2.BaseApp.

[flathubbot]

Started test build 42369

[flathubbot]

Build 42369 successful To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/40761/org.electronjs.Electron2.BaseApp.flatpakref

[bbhtt]

I don't think anyone on Flathub is using electron 3 or 7. The lowest ever I saw was the Itch IO client using Electron 10. I think it is fine to drop, cc @TingPing

[flathubbot]

Started test build 94266

[flathubbot]

Build 94266 successful To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/77015/org.electronjs.Electron2.BaseApp.flatpakref

[flathubbot]

Started test build 94274

[flathubbot]

Build 94274 successful To test this build, install it from the testing repository:

flatpak install --user https://dl.flathub.org/build-repo/77023/org.electronjs.Electron2.BaseApp.flatpakref