我尝试运行apt-get upgrade但收到许多错误消息，例如：
Setting up dovecot-core (1:2.2.33.2-1ubuntu4.8) ...
chgrp: invalid group: ‘dovecot’
dpkg: error processing package dovecot-core (--configure):
installed dovecot-core package post-installation script subprocess returned error exit status 1
dpkg: dependency problems prevent configuration of dovecot-lmtpd:
dovecot-lmtpd depends on dovecot-core (= 1:2.2.33.2-1ubuntu4.8); however:
Package dovecot-core is not configured yet.
Errors were encountered while processing:
dovecot-core
dovecot-lmtpd
clamav-base
dovecot-mysql
spamassassin
whoopsie
dovecot-sieve
clamav-daemon
sa-compile
dovecot-pop3d
dovecot-imapd
dbus
bluez
clamdscan
indicator-bluetooth
rsyslog
clamav-freshclam
policykit-1
gnome-system-log
language-selector-common
dbus-x11
udisks2
upower
dbus-user-session
gnome-terminal
avahi-daemon
indicator-power
network-manager
ubuntu-system-service
policykit-1-gnome
xdiagnose
update-notifier
aptdaemon
screen-resolution-extra
rtkit
ubuntu-desktop
gnome-keyring
gnome-disk-utility
lightdm
libapache2-mod-dnssd
avahi-utils
update-manager
brltty
accountsservice
language-selector-gnome
gnome-power-manager
gcr
packagekit
ubuntu-standard
xdg-desktop-portal
xdg-desktop-portal-gtk
Processing was halted because there were too many errors.
E: Sub-process /usr/bin/dpkg returned an error code (1)
此外，每当我尝试使用 apt-get 安装任何应用程序时，我都会收到类似的错误消息。
这是输出sudo apt update
Hit:1 http://archive.ubuntu.com/ubuntu bionic InRelease
Hit:2 http://archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:3 http://archive.ubuntu.com/ubuntu bionic-backports InRelease
Hit:4 http://archive.ubuntu.com/ubuntu bionic-security InRelease
Reading package lists... Done
Building dependency tree
Reading state information... Done
41 packages can be upgraded. Run 'apt list --upgradable' to see them.
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