gitlab:elastic:info - add indexing restrictions status

Background

The rake task currently outputs important information for support and debugging of the Advanced Search feature.

Proposal

Report status of Indexing restrictions checkbox from the Admin UI

Implementation plan

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

1. in elastic.rake, find the info task and add an output line that reports Indexing restrictions enabled using the ApplicationSetting elasticsearch_limit_indexing

      puts "Indexing restrictions enabled:\t\t#{setting.elasticsearch_limit_indexing? ? "yes" : "no"}"

2. add a new test in ee/spec/tasks/gitlab/elastic_rake_spec.rb