Upgrade to groovy failed to install "shim-signed"...

[Giuseppe C]

... forcing me to disable secureboot to have grub launched at boot.

ProblemType: Bug
DistroRelease: Ubuntu 20.10
Package: ubuntu-release-upgrader-core 1:20.10.12
ProcVersionSignature: Ubuntu 5.8.0-23.24-generic 5.8.14
Uname: Linux 5.8.0-23-generic x86_64
ApportVersion: 2.20.11-0ubuntu50
Architecture: amd64
CasperMD5CheckResult: skip
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Tue Oct 20 10:15:11 2020
InstallationDate: Installed on 2018-12-13 (676 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Release amd64 (20181017.3)
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=it_IT.UTF-8
 SHELL=/bin/zsh
RebootRequiredPkgs:
 linux-image-5.8.0-25-generic
 linux-base
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to groovy on 2020-10-19 (0 days ago)
VarLogDistupgradeAptlog:
 Log time: 2020-10-19 12:18:11.585605
 Log time: 2020-10-19 12:18:18.501112