`sudo apt autoremove` returning with error messages

After running sudo apt autoremove in order to remove packages they are no longer needed I'm getting the following messages:

EDIT

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  apg colord-data gnome-control-center-faces gnome-online-accounts libcolord-gtk1 libcolorhug2 libgsound0 libgssdp-1.2-0 libgupnp-1.2-0
  libgupnp-av-1.0-2 libgupnp-dlna-2.0-3 libieee1284-3 librygel-core-2.6-2 librygel-db-2.6-2 librygel-renderer-2.6-2 librygel-server-2.6-2
  libsane-common libsnmp-base mobile-broadband-provider-info network-manager-gnome python3-macaroonbakery python3-protobuf python3-pymacaroons
  python3-rfc3339 python3-tz rygel
0 upgraded, 0 newly installed, 26 to remove and 20 not upgraded.
1 not fully installed or removed.
After this operation, 16.7 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 296743 files and directories currently installed.)
Removing apg (2.2.3.dfsg.1-5) ...
Removing colord-data (1.4.4-2) ...
Removing gnome-control-center-faces (1:3.36.5-0ubuntu2) ...
Removing gnome-online-accounts (3.36.1-0ubuntu1) ...
Removing libcolord-gtk1:amd64 (0.2.0-0ubuntu1) ...
Removing libcolorhug2:amd64 (1.4.4-2) ...
Removing libgsound0:amd64 (1.0.2-4) ...
Removing rygel (0.38.3-1ubuntu1) ...
Removing librygel-db-2.6-2:amd64 (0.38.3-1ubuntu1) ...
Removing librygel-server-2.6-2:amd64 (0.38.3-1ubuntu1) ...
Removing librygel-renderer-2.6-2:amd64 (0.38.3-1ubuntu1) ...
Removing libgupnp-av-1.0-2 (0.12.11-2) ...
Removing libgupnp-dlna-2.0-3 (0.10.5-4) ...
Removing libieee1284-3:amd64 (0.2.11-13build1) ...
Removing libsane-common (1.0.29-0ubuntu5.2) ...
Removing libsnmp-base (5.8+dfsg-2ubuntu2.3) ...
Removing mobile-broadband-provider-info (20190618-3) ...
Removing network-manager-gnome (1.8.24-1ubuntu3) ...
Removing python3-macaroonbakery (1.3.1-1) ...
Removing python3-protobuf (3.6.1.3-2ubuntu5) ...
Removing python3-pymacaroons (0.13.0-3) ...
Removing python3-rfc3339 (1.1-2) ...
Removing python3-tz (2019.3-1) ...
Removing librygel-core-2.6-2:amd64 (0.38.3-1ubuntu1) ...
Removing libgupnp-1.2-0:amd64 (1.2.4-0ubuntu1) ...
Removing libgssdp-1.2-0:amd64 (1.2.3-0ubuntu0.20.04.1) ...
Setting up mysql-server-8.0 (8.0.26-0ubuntu0.20.04.2) ...
Renaming removed key_buffer and myisam-recover options (if present)
ERROR: Unable to start MySQL server:
mysqld: Can't read dir of '/etc/mysql/conf.d/' (OS errno 13 - Permission denied)
mysqld: [ERROR] Fatal error in defaults handling. Program aborted!
Please take a look at https://wiki.debian.org/Teams/MySQL/FAQ for tips on fixing common upgrade issues.
Once the problem is resolved, run apt-get --fix-broken install to retry.
dpkg: error processing package mysql-server-8.0 (--configure):
 installed mysql-server-8.0 package post-installation script subprocess returned error exit status 1
Processing triggers for mime-support (3.64ubuntu1) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for gnome-menus (3.36.0-1ubuntu1) ...
Processing triggers for libglib2.0-0:amd64 (2.64.6-1~ubuntu20.04.4) ...
Processing triggers for libc-bin (2.31-0ubuntu9.2) ...
Processing triggers for man-db (2.9.1-1) ...
Processing triggers for desktop-file-utils (0.24-1ubuntu3) ...
Errors were encountered while processing:
 mysql-server-8.0
E: Sub-process /usr/bin/dpkg returned an error code (1)

Entering ls -la /etc/mysql/conf.d in the Terminal is outputting

total 16
drwxr-xr-x 2 root root 4096 Sep 13 17:26 .
drwxr-xr-x 4 root root 4096 Sep 13 17:26 ..
-rw-r--r-- 1 root root    8 Aug  3  2016 mysql.cnf
-rw-r--r-- 1 root root   55 Aug  3  2016 mysqldump.cnf

and entering lsattr /etc/mysql/conf.d in the Terminal is outputting

--------------e----- /etc/mysql/conf.d/mysqldump.cnf
--------------e----- /etc/mysql/conf.d/mysql.cnf

while lsattr -d /etc/mysql/conf.d is outputting

lsattr: Inappropriate ioctl for device While reading flags on /etc/mysql/conf.d

Also, sudo apt update gives

Ign:1 cdrom://Ubuntu 18.04.3 LTS _Bionic Beaver_ - Release amd64 (20190805) bionic InRelease
Hit:2 cdrom://Ubuntu 18.04.3 LTS _Bionic Beaver_ - Release amd64 (20190805) bionic Release
Get:3 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Hit:4 http://dl.google.com/linux/chrome/deb stable InRelease                                                                                         
Hit:6 http://archive.ubuntu.com/ubuntu focal InRelease                                                                                               
Hit:7 http://ppa.launchpad.net/mkusb/ppa/ubuntu bionic InRelease
Get:8 http://archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Get:9 http://security.ubuntu.com/ubuntu focal-security/main amd64 DEP-11 Metadata [27.6 kB]
Get:10 http://security.ubuntu.com/ubuntu focal-security/universe amd64 DEP-11 Metadata [61.1 kB]
Get:11 http://security.ubuntu.com/ubuntu focal-security/multiverse amd64 DEP-11 Metadata [2464 B]
Get:12 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [282 kB]
Get:13 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 c-n-f Metadata [14.2 kB]
Get:14 http://archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata [353 kB]
Get:15 http://archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata [944 B]
Fetched 969 kB in 1s (650 kB/s)                                            
Reading package lists... Done
Building dependency tree       
Reading state information... Done
20 packages can be upgraded. Run 'apt list --upgradable' to see them.