Interrapt G26

Description.
This field is supposed to met minimum character limit of 3 characters and a maximum limit of 25 characters for the mentor's surname. The app currently allows users to create new mentors with more than 25 characters in their surname.

Steps to reproduce
1. Login on interrapt
2. Open Mentors from the sidebar
3. Click create
4. In the surname field enter a surname with more than 25 characters (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)
5. Fill all the other fields
6. Click on Create

Expected result
New mentor should not be created, message in red letters should be displayed telling the user surname field is required with red letters
Actual result
The mentor is crated with more than 25 characters without providing the error feedback that criteria is not met.