BUGFIX - whats new dropdown text wraps on ubuntu

This fixes the issue linked to below. I've opted to use flexbox better
align the notification count and the text in the dropdown item.

part of:
https://gitlab.com/gitlab-org/customers-gitlab-com/-/issues/2507

ee/app/views/layouts/header/_whats_new_dropdown_item.html.haml

 - if ::Feature.enabled?(:whats_new_dropdown, current_user)
   - if ::Feature.enabled?(:whats_new_drawer, current_user)
     %li
-      %button.js-whats-new-trigger{ type: 'button', data: { storage_key: whats_new_storage_key } }
+      %button.gl-justify-content-space-between.gl-align-items-center.js-whats-new-trigger{ type: 'button', data: { storage_key: whats_new_storage_key }, class: 'gl-display-flex!' }
         = _("See what's new at GitLab")
-        %span.js-whats-new-notification-count.whats-new-notification-count.gl-ml-4
+        %span.js-whats-new-notification-count.whats-new-notification-count
           = whats_new_most_recent_release_items_count
   - else
     %li

ee/changelogs/unreleased/jswain_whats_new_wrapping_bugfix.yml

+---
+title: BUFIX - whats new dropdown text wraps on ubuntu
+merge_request: 51510
+author:
+type: fixed