discover-backend-apk: does not find all system updates
When updating the system with Discover, some updates are missed.
For example, Discover says my system is up to date, but apk list -u
shows 3 pending updates:
$ apk list -u
alsa-lib-dev-1.2.4-r2 x86_64 {alsa-lib} (LGPL-2.1-or-later) [upgradable from: alsa-lib-dev-1.2.3.2-r1]
kde-cli-tools-5.21.3-r0 x86_64 {kde-cli-tools} ((GPL-2.0-only OR GPL-3.0-only) AND GPL-2.0-or-later AND GPL-2.0-only AND LGPL-2.1-only) [upgradable from: kde-cli-tools-5.20.5-r1]
alsa-lib-1.2.4-r2 x86_64 {alsa-lib} (LGPL-2.1-or-later) [upgradable from: alsa-lib-1.2.3.2-r1]