AO3-7120 Change user troubleshooting to also reindex user in admin user search

[Cubostar]

Pull Request Checklist

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• Have you read the contributing guidelines?
• Have you added tests for any changed functionality?
• Have you added the Jira issue number
  as the first thing in your pull request title (e.g. AO3-1234 Fix thing)
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Issue

https://otwarchive.atlassian.net/browse/AO3-7120

Purpose

This PR makes the Troubleshoot button in the admin user also reindex the user.

Credit

Cubostar, he/him

[sarken]

The issue mentions this will rely on automated testing, not manual, so I'm going to mark this as Action Needed until automated tests are added.

[Bilka2]

Please also update the "To fix common errors with this user's Subscriptions and Stats pages..." note on the user administration page to mention the admin user search

[Bilka2]

As I said in my previous comment, please update the troubleshooting help text on the admin user page. It should say

To fix common errors with this user's Subscriptions and Stats pages, and to reindex the user and their works and bookmarks, choose "Troubleshoot."

[Bilka2]

please call enqueue_to_index instead, we don't need to do this reindexing synchronously and it matches what reindex_user_creations does. you can then check that it was queued with add_to_reindex_queue in the rspec test