Stick the line numbers left when scrolling

ee/app/assets/javascripts/vulnerabilities/components/vulnerability_file_content_viewer.vue

@@ -73,7 +73,9 @@ export default {
       :class="userColorScheme"
       class="code blob-viewer file-content gl-flex gl-items-center gl-overflow-auto gl-rounded-base"
     >
-      <div class="line-numbers diff-line-num gl-border-r !gl-min-w-5 !gl-pl-3 !gl-pr-0">
+      <div
+        class="line-numbers diff-line-num gl-border-r gl-sticky gl-left-0 gl-z-1 !gl-min-w-5 !gl-pl-3 !gl-pr-0"
+      >
         <a
           v-for="line in lineNumbers"
           :id="`NUM-MARKER-${line.stepNumbers}-L${line.lineNumber}`"