Draft: Fix error response messages and validation logic in Events Service
Proposers
- Afonso Castanheta (ITAV)
Description
This MR addresses an inconsistency in the CAPIF Events API when deleting a non-existent event subscription. Previously, the API returned a 401 Unauthorized error; this MR updates the response to 404 Not Found with a clearer message. The related Robot Framework test is also updated to expect the new response, ensuring alignment between implementation and test.