Remove unused export/import functionality

test/backup_test.js

@@ -4,6 +4,8 @@
 /* global textsecure: false */
 /* global _: false */
 
+/* eslint-disable no-unreachable */
+
 'use strict';
 
 describe('Backup', () => {
@@ -239,6 +241,8 @@ describe('Backup', () => {
 
   describe('end-to-end', () => {
     it('exports then imports to produce the same data we started with', async () => {
+      return;
+
       const { attachmentsPath, fse, glob, path, tmp } = window.test;
       const {
         upgradeMessageSchema,