Description of the need

When looking to see the list of available updates, I usually first try going to Admin > Functionality > Update Modules. This is not helpful, especially if the server doesn't support automatic updates, and all you see is an error message.

It would be good to provide a link to the available updates status report to help people get to the right place.

Proposed solution

Display a message like this at the top of the page:

For version information and update status for all installed modules, see the available updates report.

GitHub Link: 
https://github.com/backdrop/backdrop-issues/issues/4471
GitHub Issue #: 
4471