Per our conversation with @jcrespo:
First, `modules/mysql` isn't used by core databases (in favor of `modules/mariadb`) and is unmaintained. It perhaps could be fully removed and replaced by the `mariadb` module), but it currently has these users in the tree:
```
[] hieradata/labs.yaml:mysql::server::use_apparmor: false # The images we have for debian don't support it
[] modules/mediawiki_singlenode/manifests/init.pp: class { '::mysql::server':
[x] modules/rolequarry/manifests/requesttracker/labsdatabase.pp: class { '::mysql::server':
[x] modules/role/manifests/requesttracker/labs.pp: require => Class['::requesttracker',class { 'mysql::server'],:
[x] modules/role/manifests/simplelamprequesttracker/labs.pp: class { ':: require => Class['::requesttracker', 'mysql::server':],
[] modules/role/manifests/statistics/privatesimplelamp.pp: mysql::config::clientclass { 'statistics-private':::mysql::server':
[] modules/role/manifests/wikimetrstatistics/stagingprivate.pp: classmysql::config::client { '::mysql::server':statistics-private':
[] modules/statisticsrole/manifests/compute.pp: mysql::config::clientwikimetrics/staging.pp: class { 'stats-research':::mysql::server':
[] modules/statistics/manifests/discoverycompute.pp: :: mysql::config::client { 'discovery-stats':stats-research':
[] modules/statistics/manifests/mysql_credentialsdiscovery.pp: ::mysql::config::client { $title:'discovery-stats':
[] modules/statistics/manifests/mysql_credentials.pp: mysql::config::client { $title:
[] modules/statistics/manifests/wmde.pp: mysql::config::client { 'research-wmde':
```
Second, mariadb::packages_wmf and mariadb::packages should probably be merged into one.
Plus, any other cleanups that we need to do while (if?) we're repurposing the mariadb module to cover misc use cases :)