Interrapt G26

In the "Bio" section for mentors, the character should be minimum 20 characters, the system allow user to create the mentor with less that 20 characters

Steps to Reproduce:
1.Log in to interrpat
2.Click on "Mentors" from the side bar menu
3.Click on "Create" button
3.Enter Name, Surname and Email
4.Enter Bio with less than 20 characters
5.Enter Occupation
6.Click on "Create" button

Expected Results:
The application should show the error message "The Bio must be at least 20 characters".

Actual Results:
Тhe mentor is created, with bio less than 20 characters.