Revert "ci: try build appimage on ubuntu 18.04" #968

Job	Run time
Windows (windows, 2022, 6.7.3, qt5compat, win64_msvc2019_64, x64, -x64, windows-x64-qt6)	16m 55s
Mac (macos, 13, 6.7.3, clang_64, qt5compat, x64, macos-intel-qt6, -DKLOGG_OSX_DEPLOYMENT_TARGET=1...	28m 31s
Windows (windows, 2022, 5.15.2, win32_msvc2019, x86, windows-x86-qt5)	10m 52s
Linux (oraclelinux, 8, x64, yum install -y --setopt tsflags=test /usr/local/klogg*.rpm, RPM, orac...	15m 31s
SaveVersion	4s
Mac (macos, 14, 6.7.3, clang_64, qt5compat, arm64, macos-arm-qt6, -DKLOGG_OSX_DEPLOYMENT_TARGET=1...	12m 6s
Linux (ubuntu_focal, 20.04, x64, apt-get update && apt install --dry-run /usr/local/klogg*.deb, D...	14m 42s
Linux (ubuntu_jammy, 22.04, x64, apt-get update && apt install --dry-run /usr/local/klogg*.deb, D...	12m 55s
Linux (ubuntu_noble, 24.04, x64, apt-get update && apt install --dry-run /usr/local/klogg*.deb, D...	15m 22s
Linux (ubuntu_appimage, 20.04, x64, appimage, AppImage, docker/ubuntu20.04, variar/klogg_ubuntu20...	19m 4s
	2h 26m 2s

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