Use the latest LTS version of MySQL.

Author: desrosj

.github/workflows/phpunit-tests.yml

@@ -170,7 +170,7 @@ jobs:
         os: [ ubuntu-latest ]
         php: [ '8.3' ]
         db-type: [ 'mysql' ]
-        db-version: [ '8.0' ]
+        db-version: [ '8.4' ]
         multisite: [ false ]
         memcached: [ false ]
         phpunit-test-groups: [ 'html-api-html5lib-tests' ]