GREG-113: Making some fields non-null to better handle them in form

frontend/src/routes/guest/register/enteredGuestData.ts

@@ -8,8 +8,8 @@ export type EnteredGuestData = {
   lastName: string
   mobilePhoneCountry: string
   mobilePhone: string
-  nationalIdNumber?: string
-  passportNumber?: string
-  passportNationality?: string
+  nationalIdNumber: string
+  passportNumber: string
+  passportNationality: string
   dateOfBirth?: Date
 }