Fix registrar cannot invite employees

Closes #388 (closed)

app/models/company.rb

@@ -50,7 +50,7 @@ class Company < ApplicationRecord
   # @param user [User] the user
   # @return [Boolean] whether the given user is involved in (employee of) this company
   def involved?(user)
-    user.has_any_role?({ name: :registrar, recource: self },
+    user.has_any_role?({ name: :registrar, resource: self },
                        { name: :employee, resource: self },
                        { name: :unconfirmed_employee, resource: self })
   end