Background:
After a new release migration tests usually fail as we have no new upgrade setup in place.

AT:

• upgrade/migration tests should support getting migrated to support a new version during release automatically
  • qa/upgrade-optimize-data
  • qa/upgrade-es-schema-tests
    • are they even needed still?
  • upgrade - IT's
• the previous.generator.version in the upgrade-optimize-data module is adjusted automatically to the previous version (see here for more information)