Added price currency to conference, select currency in basic info and created data rake task for setting old conferences' price currency

lib/tasks/set_conference_currency.rake

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+namespace :data do
+  desc 'Sets price_currency in all pre-existing Conference records'
+  task set_conference_price_currency: :environment do
+    Conference.all.each do |conference|
+      # if ticket has price_currency it is old and needs to be updated
+      if conference.tickets.first.price_currency
+        # check all tickets have same price currency
+        ticket_pc = conference.tickets.first.price_currency
+        make_change = true
+        conference.tickets.each do |ticket|
+          make_change = false unless ticket.price_currency == ticket_pc
+        end
+      end
+      if make_change
+        conference.update(price_currency: ticket_pc)
+        puts "price currency of #{ticket_pc} set for conference: #{conference.title}."
+      else
+        puts "price currency discrepancy between tickets for conference: #{conference.title}, please check and try again."
+      end
+    end
+  end
+end