Job Title not accepted on working group application endpoint

We need to capture the job titles of the contacts in the working group application.

Currently, a contact has the following schema:

 {
  "user": null,
  "first_name": null,
  "last_name": null,
  "working_group_alias": "string",
  "working_group_level": "string",
  "mail": null,
  "is_signing_authority": true
 }

But the following is expected (job_title property):

 {
  "user": null,
  "first_name": null,
  "last_name": null,
  "job_title": "string",
  "working_group_alias": "string",
  "working_group_level": "string",
  "mail": null,
  "is_signing_authority": true
 }