Please never run apt upgrade
The notation is confusing, but apt upgrade only upgrade packages which don’t require to install/remove additional dependencies. But in the context of upgrading the entire system to a new debian version, it’s likely that a lot of packages need to install/remove dependencies to upgrade.
This behavior is mainly historical (though I could be wrong) because it was considered “less safe” to install/remove dependencies.
Nowadays it’s really safe and in fact “safer” (because not upgrading all packages together may create inconsistencies) to upgrade all packages with apt dist-upgrade
apt dist-upgrade, as opposed to what the name suggest is not about “upgrading the distribution” as if it was meant only for major debian upgrades … it just means that it will also upgrade packages that need to remove/install dependencies
Anyway, TL;DR: just run apt dist-upgrade (or apt full-upgrade, it’s the same thing), get less troubles
And in the context of YunoHost, it would even be better to run yunohost tools upgrade system