[Auth](ft/tests): Add unit test for indexer
[Auth](ft/tests): Add unit test for indexer

- Add unit test for lib/auth/in_memory/index.js

tomateos/S3,lucisilv/Silviu_S3-Antidote,lucisilv/Silviu_S3-Antidote,truststamp/S3,lucisilv/Silviu_S3-Antidote,truststamp/S3,tomateos/S3,scality/S3,lucisilv/Silviu_S3-Antidote,lucisilv/Silviu_S3-Antidote,scality/S3,scality/S3,truststamp/S3,tomateos/S3,scality/S3,tomateos/S3,lucisilv/Silviu_S3-Antidote,truststamp/S3,scality/S3,lucisilv/Silviu_S3-Antidote,lucisilv/Silviu_S3-Antidote,truststamp/S3,truststamp/S3,tomateos/S3,scality/S3,scality/S3,truststamp/S3,tomateos/S3,tomateos/S3,truststamp/S3,scality/S3,tomateos/S3