Adjust stick elements at top of merge request

- Unstickied changes count bar (so it doesn't always show when scrolling down)
- Restored stickiness of tabs bar (so DOES always show when scrolling down)

Author: AustonZ

css/style.css

@@ -123,4 +123,16 @@
 .gitlab-tree-plugin-file-commented-icon
 {
     margin-right: 7px;
-}
+}
+
+.gitlab-tree-tabs-wrapper
+{
+    top: 40px;
+    z-index: 200;
+    position: sticky;
+}
+
+.diff-files-changed {
+    position: inherit !important;
+}
+