Add indexing restrictions status in gitlab:elastic:info

What does this MR do and why?

This MR will add the Indexing restrictions enabled status as either yes or no

Screenshots or screen recordings

How to set up and validate locally

You should have your development environment setup to have Elasticsearch and Advanced Search enabled

Run the rake task

bundle exec rake gitlab:elastic:info

You will see the value of Indexing restrictions enabled:

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #386912 (closed)