Configure Event: Registration tab - fix content and display of alert message for Allow multiple

When checking the 'Allow multiple registrations from the same email address?' box, a status message is displayed which is populated from [$ruleFields}.

In an upgraded 4.2 DB with the Unsupervised Individual rule updated to be the 'Name and Email (reserved)', the ruleFields variable contains this unexpected value:

["First Name","Last Name","Email","Organization Name","Email","Household Name","Email","Email","Organization Name","Email","Household Name","Email","First Name","Last Name","Street Address","Middle Name","Suffix Id"]