Confirm change process

New flow to confirm changes with a URL and update an OTRS to notify the confirmation.

Process:

1. OTRS creates a URL with OV base url + /confirm-change/ + IDOV (OV process identifier)
2. OTRS sends an email with this URL
3. The user access to the URL
4. The OV response to this URL with a Thanks view
5. OV search the ticket in OTRS using the IDOV
6. Update the ticket if it is valid, else raise an exception, printing the error in the log and showing the error to the user.

Merged !50 (closed) because has a lot of conflicts with that MR.