Add migration for application going public event it has isPublic false set

Editor assessment

The subject attempts to state the migration: an application going public even though it has isPublic false set, with even misspelled as event, which initially scrambles the sentence. The fix type matches a data-correction migration. No scope is present. There is no body to explain how such rows arose or what the migration rewrites, so the reader gets the condition but not the correction logic. No footers appear. The typo is the main offender in an otherwise specific defect description.