add previous privacy notice

server/xpub-model/seeds/europepmc.js

@@ -28,6 +28,7 @@ exports.seed = async (knex, Promise) => {
 
   // Seed versions
   await knex('privacy_notice').insert([
+    { version: 2, effective_date: new Date('2018-05-24') },
     { version: 3, effective_date: new Date('2018-08-23') },
   ])
 }