Potential fix for code scanning alert no. 2: Replacement of a substring with itself

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

static/js/messages.js

@@ -140,7 +140,7 @@ document.addEventListener("DOMContentLoaded", async function () {
 
     function formatMessageTimestamp(createdAt) {
         const date = new Date(createdAt);
-        return date.toLocaleString('sv-SE', { hour12: false }).replace(' ', ' ').slice(0, 16);
+        return date.toLocaleString('sv-SE', { hour12: false }).slice(0, 16);
     }
 
     await fetchMessages();