Fix html in order to make items accessible through keyboard navigation

Adds CHANGELOG entry

Adds MR ID to CHANGELOG entry

app/views/groups/new.html.haml

@@ -21,5 +21,5 @@
       = render 'shared/group_tips'
 
   .form-actions
-    = f.submit 'Create group', class: "btn btn-create", tabindex: 3
+    = f.submit 'Create group', class: "btn btn-create"
     = link_to 'Cancel', dashboard_groups_path, class: 'btn btn-cancel'

app/views/shared/_choose_group_avatar_button.html.haml

-%a.choose-btn.btn.btn-sm.js-choose-group-avatar-button
+%button.choose-btn.btn.btn-sm.js-choose-group-avatar-button
   %i.fa.fa-paperclip
   %span Choose File ...
  

changelogs/unreleased/26238-buttons-not-accessible.yml

+---
+title: Fixes buttons not being accessible via the keyboard when creating new group
+merge_request: 8469
+author: