This is a backport of electrum#7785 and electrum#10019
Depends on D19001
build appimage: bump pkg2appimage version
should fix https://github.com/spesmilo/electrum/issues/7784
by including commit https://github.com/AppImage/pkg2appimage/commit/1e3ecde6b92ef198405463415b8090a4435d0cb0
Updates the appimage build scripts to use the newer
https://github.com/AppImage/appimagetool tool to bundle the appimage
instead of the discontinued https://github.com/AppImage/AppImageKit.
To prevent the new appimagetool from downloading a random "latest"
appimage runtime (type2-runtime) binary this PR also adds
functionality to clone and build
https://github.com/AppImage/type2-runtime from source. This is done
using the build scripts provided in the type2-runtime repository,
however the Dockerfile they use for building is replaced by a copy with
pinned package versions to prevent issues with reproducibility.This should fix the issue of missing libfuse2 which users of the appimage
have on "modern" distributions.
The new type2-runtime is statically linked and includes the required
dependencies now instead of relying on the host to provide it.