Add unit tests for restore (#62)

* Move archive file size to utils

* Disable net connect with nock

* Add unit tests for restore

* Fix test names and test URL

jest.config.js

@@ -1,3 +1,5 @@
+require('nock').disableNetConnect();
+
 module.exports = {
   clearMocks: true,
   moduleFileExtensions: ['js', 'ts'],