実際のところ
$ sudo apt upgrade E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem.
dpkg を直接叩いてゴミを片付けないといけません。
$sudo dpkg --configure -a Setting up libmono-system-servicemodel-internals0.0-cil (6.10.0.104-0xamarin16+raspbian10b1) ... ...
参考もと
- man dpkg
