#9144: Credentials - Duplicates Created if Credentials is Linked to 2 Courses

New Service Desk Issue(s): ION-1351

If multiple courses provide staff with the same credential, the system correctly prompts user if they wish to 'Add New' or 'Update Existing' credential records. If selecting 'Add New' a second credential record of that specific type is created. If 'Update Existing' is selected, the previous credential record is set to a status of Historical and the new one as Current.