Merge branch 'gt-add-transparent-background-to-markdown-header-tabs' into 'master'

Add transparent background to markdown header tabs

Closes #53105

See merge request gitlab-org/gitlab-ce!22565

app/assets/stylesheets/framework/secondary_navigation_elements.scss

@@ -37,6 +37,7 @@
 
     button {
       padding-top: 0;
+      background-color: transparent;
     }
 
     &.active a,

changelogs/unreleased/gt-add-transparent-background-to-markdown-header-tabs.yml

+---
+title: Add transparent background to markdown header tabs
+merge_request: 22565
+author: George Tsiolis
+type: fixed