User limit enforcement (#26511)

* Added hard limits when creating user

* Added check to user activation

* Added missing check for licensed servers

* Fix i18n

* Fixed style order

* Added a separate hard limit along with existing 10k user soft limit

* For CI

* Fixing flaky test, hopefully

* Added tests

webapp/channels/src/components/admin_console/system_users/system_users.scss

@@ -60,10 +60,15 @@ table.systemUsersTable {
                 }
 
                 .error {
+                    max-width: 300px;
                     align-self: start;
                     grid-area: error;
 
                     @include textElipsis;
+
+                    // this need to be here, after textElipsis because
+                    // we need to override white-space property coming from the mixing
+                    white-space: normal;
                 }
             }