ok I get you now.
it does include module_hotfixes=1
cat /etc/yum.repos.d/MariaDB.repo
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.4/centos8-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1
priority=1
module_hotfixes=1
any other things you could suggest, please?