Merge branch 'winh-collapsed-sidebar-scrolling' into 'master'

Prevent horizontal scrolling in new sidebar when collapsed

Closes #36608 and #36507

See merge request !13638

app/assets/stylesheets/new_sidebar.scss

@@ -104,6 +104,10 @@ $new-sidebar-collapsed-width: 50px;
   &.sidebar-icons-only {
     width: $new-sidebar-collapsed-width;
 
+    .nav-sidebar-inner-scroll {
+      overflow-x: hidden;
+    }
+
     .badge,
     .project-title {
       display: none;