Context:
The API implemented with OPT-6393 needs to be added to the existing backup docs section (https://docs.camunda.io/docs/self-managed/backup-restore/optimize-backup/ )

API details: https://docs.google.com/document/d/1K1YLFi502FauH2gvZD2fzkPIKKnK1w9fT9SZJL4oSn0/edit#heading=h.ab4lg5i02f 

AT:

• delete API is documented
  • includes path
  • includes responses
  • includes example request