Add missing tooltip and aria-label for commit description toggle

Changelog: fixed

app/assets/javascripts/diffs/components/commit_item.vue

@@ -155,9 +155,11 @@ export default {
 
             <gl-button
               v-if="commit.description_html && collapsible"
+              v-gl-tooltip
               class="js-toggle-button"
               size="small"
               icon="ellipsis_h"
+              :title="__('Toggle commit description')"
               :aria-label="__('Toggle commit description')"
             />
 

app/views/projects/commits/_commit.html.haml

@@ -34,7 +34,7 @@
         ·
         = commit.short_id
       - if commit.description? && collapsible
-        %button.gl-button.btn.btn-default.button-ellipsis-horizontal.btn-sm.gl-ml-2.text-expander.js-toggle-button
+        %button.gl-button.btn.btn-default.button-ellipsis-horizontal.btn-sm.gl-ml-2.text-expander.js-toggle-button{ data: { toggle: 'tooltip', container: 'body' }, :title => _("Toggle commit description"), aria: { label: _("Toggle commit description") } }
           = sprite_icon('ellipsis_h', size: 12)
 
       .committer