Group Message view crashes when empty. [#3275650]

Problem/Motivation

When you open the 'Messages' page of a Mail Group without any messages, the page fails.

TypeError: Drupal\views\Plugin\views\field\EntityOperations::getEntityTranslation(): Argument #1 ($entity) must be of type Drupal\Core\Entity\EntityInterface, null given, called in /var/www/html/web/core/modules/views/src/Plugin/views/field/EntityOperations.php on line 130 in Drupal\views\Plugin\views\field\EntityOperations->getEntityTranslation() (line 69 of core/modules/views/src/Entity/Render/EntityTranslationRenderTrait.php).

Steps to reproduce

Create a new Mail group
Open the Mail group's Messages page.

Proposed resolution

Make the 'Message' relationship on the mandatory on the View used to build the page. Thus, there won't be a View results if there are no messages to show.

Issue fork mailgroup-3275650

Show commands

Start within a Git clone of the project using the version control instructions.

Add & fetch this issue fork’s repository

Or, if you do not have SSH keys set up on git.drupalcode.org:

Add & fetch this issue fork’s repository

3275650-group-message-view changes, plain diff MR !4
Check out this branch for the first time

Check out existing branch, if you already have it locally