Mirage is Injecting the appbase Bearer Authorization token into non-appbase Elasticsearch cluster requests

[mschnee]

This is the cause of #16

Reproduction steps:

• Install mirage as an extension or run it locally.
• Provide an AWS-hosted ElasticSearch cluster URL and index.
• Note in the web inspector of your choice that the request to ${host}/${index}/_mapping includes an Authorization header, which causes the request to fail.
• This Authorization header should not be sent.

[siddharthlatest]

@mschnee Thanks for pointing this out. I have an idea on what's causing this. @metagrover @lakhansamani Is it possible to upgrade Mirage to use the latest appbase-js lib?