[neon-notifications] Dev Required: assimp - 5.2.1

[Neon CI]

https://build.neon.kde.org/job/watcher_release_backports-focal_assimp/58/display/redirect

#<Debian::UScan::DEHS::Package:0x00005592ff2ca460 @name="assimp", @debian_uversion="5.2.0~ds0", @debian_mangled_uversion="5.2.0", @upstream_version="5.2.1", @upstream_url="https://github.com/assimp/assimp/archive/refs/tags/v5.2.1.tar.gz", @status="Newer version available">