Context:
As Event based processes have been officially released with 3.0.0 we need to ensure they still work after the migration to 3.1.0 and future migrations.

AT:

• the generator used in the `Data upgrade test` build stage creates all sorts of event related data
  • ingested events
  • camunda event data
  • event based process mappings
  • event based process instances
  • event based process reports

Out of scope:
Due to the existing Optimize 3.0.0 generator not adding event data yet and due to it not supporting auto-generation the extension of the PostMigrationTests is descoped and will be handled with OPT-3968 ensuring regression tests going forward. For the Optimize 3.1.0 migration we will rely on manual testing as aprt of the release testing.