Error accessing unknown fields on JPA entity during active session

[EhsanEhrari]

When attempting to create a new user without selecting a partner from the dropdown menu, the system throws an error message:

**org.tctalent.server.util.dto.DtoBuilderException: Error while accessing property 'firstName' on User$HibernateProxy$9fd3g8HE** Additionally, even though the error occurs, the user is still registered in the database. Upon further investigation, I found that after selecting a partner, the system does not allow the creation of the user as it already exists in the database due to the incomplete creation process.

Steps to Reproduce:

1. Log in as a System Admin.
2. Navigate to the User Creation page.
3. Attempt to create a new user without selecting a partner from the dropdown menu.
4. Observe the error message mentioned above.
5. Note that despite the error, the user is still registered in the database.
6. Try to complete the user creation process by selecting a partner, and observe that the system does not allow the creation due to existing user data in the database.

[EhsanEhrari]

Proposed Solutions:

• The Save button should remain inactive if a partner is not specified. However, it's crucial to ensure that the server handles bad data it receives more gracefully.
• The server should throw an exception if no partner is specified instead of attempting (unsuccessfully) to apply a default partner.