Show review assignments in submission summary panel

[NateWr]

Describe the problem you would like to solve
Editors want to be able to see more information about review assignments without leaving the submissions list so that they can more quickly manage many submissions.

Describe the solution you'd like
Add the list of review assignments to the submission summary panel. All review assignments should be shown here, including declined or cancelled reviews.

Who is asking for this feature?
This was a recommendation after user tests for #7495.

Additional information
The following mockup shows where the review assignments might appear in the submission summary panel. More work needs to be done to finalize the design, unless the existing review grid is used.