MySQL Dump on Ubuntu 20.04 returns 0 byte file and runs indefinitely. Works on Ubuntu 18.04

I am using identical configs on Ubuntu 20.04 as I was previously on 18.04; however, on 20.04 the CPU shoots up to 50% usage and the process runs indefinitely, and by indefinitely I mean it was running for over 24hr when I caught the issue. I am completely stumped on why this is not working on 20.04. Mysqldump is installed using the following command:

sudo apt-get update
sudo apt-get install -y --no-install-recommends mysql-client

Output of mysqldump -V Ubuntu 20.04:

mysqldump  Ver 8.0.27-0ubuntu0.20.04.1 for Linux on x86_64 ((Ubuntu))

Output of mysqldump -V Ubuntu 18.04:

mysqldump  Ver 10.13 Distrib 5.7.36, for Linux (x86_64)

Terminal command:

sudo mysqldump --defaults-file=/var/mysqldump/conf.cfg test_db | gzip > /var/tmp/backup.gz

Contents of conf.cfg:

[client]
host=xxx
user=xxx@db
password=xxx

[mysqldump]
quick
single-transaction
skip-lock-tables

Why would this work on Ubuntu 18.04, but fails indefinitely while consuming CPU resources on 20.04? Is there a settings change on 20.04 that I have overlooked?