OptaWeb Employee Rostering: docker image DDL exceptions when running on a real database

"#1 weird ddl related exception during 1st time startup using a new external DB. Even it seems not causing too much issue in application itself, but it's a huge pile of logs hard to ignore."

Reqs:

• Run optaweb-employee-rostering with a postgresql and mysql instead of H2. Look at the console output. One of the relation tables with employee (employee_skill??) isn't looking good.
• Fix it by adding an annotation that specifies the name of that table?