feat(search-index): add retry for search index create and settings update

[rs-amp]

This PR adds a method that allows requests that create or modify resources and are guaranteed to go through to wait for their results to come through if the initial request is to time out.

This method has been added to:

• search index create - Creating indexes can be slow, but if you make the request you can guarantee the index will be created.
• search index settings update: It can create replicas, this can be slow for a similar reason.

This hasn't been heavily tested since it can be hard to trigger. Will be going though QA to verify.