Fix issues in mastercard record created out of index case forms

The index case registration and demographic update forms need an update to fix the following issues:

1. When the relationship type Mae/Pai is select for a contact person, the relation type is not eventually shown in the mastercard record created in EPTS. It works well when other relationship types are selected.
2. Pre-existing relationships are created as new mastercard records, creating potential duplication of entries in the mastercard