[VkBridge] Revert more universal regex for title generation (#3736)

In practice it lead to feed items to have "untitled".
Using previous regex with more covered cases.

Credits to https://t.me/votkot as author of regex

bridges/VkBridge.php

@@ -453,7 +453,7 @@ class VkBridge extends BridgeAbstract
     {
         $content = explode('<br>', $content)[0];
         $content = strip_tags($content);
-        preg_match('/.+?(?=[\.\n])/mu', htmlspecialchars_decode($content), $result);
+        preg_match('/^[:\,"\w\ \p{L}\(\)\?#«»\-\–\—||&\.%\\₽\/+\;\!]+/mu', htmlspecialchars_decode($content), $result);
         if (count($result) == 0) {
             return 'untitled';
         }