Release evidence documentation

What does this MR do?

Documentation for #38103 (closed)

Related issues

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• Follow the Documentation Guidelines and Style Guide.
• [-] If applicable, update the permissions table.
• Link docs to and from the higher-level index page, plus other related docs where helpful.
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/label documentation

doc/user/project/releases/index.md

@@ -255,15 +255,27 @@ Please note that Release Evidence's data is collected regardless of this
 feature flag, which only enables or disables the display of the data on the
 Releases page.
 
-### Scheduled Evidence Creation
+### Scheduled Evidence creation
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/23697) in GitLab 12.8.
 
 When the `released_at` date and time is not provided, the date and time of Release
 creation is used. The Evidence collection background is immediately executed.
 
-If a future `released_at` is specified, the Release is an **Upcoming Release**. In this
+If a future `released_at` is specified, the Release becomes an **Upcoming Release**. In this
 case the Evidence is scheduled to be collected at the `released_at` date and time, via a
 background job.
 
 If a past `released_at` is used, no Evidence is collected for the Release.
+
+<!-- ## Troubleshooting
+
+Include any troubleshooting steps that you can foresee. If you know beforehand what issues
+one might have when setting this up, or when something is changed, or on upgrading, it's
+important to describe those, too. Think of things that may go wrong and include them here.
+This is important to minimize requests for support, and to avoid doc comments with
+questions that you know someone might ask.
+
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