The warning banner is displayed on the partner form view if another partner:
- has the same e-mail address (independantly from the case, from starting spaces and ending spaces),
- is not the parent nor the child of the partner,
- if the partner is attached to a specific company: is in the same company or is not attached to a specific company,
- if the partner is not attached to a specific company: is in any company or not attached to a specific company.