Drush command "eshr" should have label changed

Problem/Motivation

The drush command "eshr" has a label that says "Re-indexes entities associated with an Elasticsearch index plugin."

This is wrong, since running that command means / may mean that the entities have been added to a queue, instead of indexing right now.

I have been hitting "drush eshr" several times now and wondering why my content is not indexed :)

Steps to reproduce

* Run "drush eshr"
* See that your content is not re-indexed :)

Proposed resolution

Mention in the label that this command (may) add the entities to a queue.