Removing users from deleted class - no need to show error message here about the class

The problem with showing an error here is that the removal can be
partially successful. The error doesn't show up when removing, but
rather when undoing the removal - these changes simply proceed along as
if everything went okay because ... you're removing users from the class
and, technically, they've already been removed from the class :)

Author: nucleogenesis

kolibri/plugins/facility/assets/src/views/users/sidePanels/RemoveFromClassSidePanel.vue

@@ -268,14 +268,20 @@
             kind: UserKinds.COACH,
           }))
           : [];
-        await Promise.all([
-          enrollments.length
-            ? MembershipResource.saveCollection({ data: enrollments })
-            : Promise.resolve(),
-          assignments.length
-            ? RoleResource.saveCollection({ data: assignments })
-            : Promise.resolve(),
-        ]);
+        try {
+          await Promise.all([
+            enrollments.length
+              ? MembershipResource.saveCollection({ data: enrollments })
+              : Promise.resolve(),
+            assignments.length
+              ? RoleResource.saveCollection({ data: assignments })
+              : Promise.resolve(),
+          ]);
+        } catch (_) {
+          showErrorWarning.value = true;
+        } finally {
+          loading.value = false;
+        }
         props.onChange({
           affectedClasses: selectedOptions.value,
           resetSelection: true,