fleshed out publish date

frontend/components/PostHeader.tsx

@@ -17,7 +17,7 @@ export const PostHeader = function PostHeader({ post }: PostHeaderOpts) {
               </p>
               <p class="text-md font-medium text-[#E39A9C] sm:text-xl italic">
                 by {post.first_name} {post.last_name} posted on{" "}
-                {convertUtc(post.created_at)}
+                {convertUtc(post.publish_date)}
               </p>
             </div>
           </div>