config: Fix 84c3b9a for Styx 4.5.0 which accidentally merged Styx 5 P…

…HP 8+ changes

serendipity_config.inc.php

@@ -488,7 +488,7 @@
 // NO, NOT on MYSQL alike databases for use of fulltext extended search operators !!!
 // Make sure this variable is always properly sanitized, though it should have gone through routing taking care before. Previously in compat.inc.php, but there LANG_CHARSET was not defined.
 if (isset($serendipity['GET']['searchTerm']) && $serendipity['dbType'] !== 'mysqli') {
-    $serendipity['GET']['searchTerm'] = htmlspecialchars(strip_tags((string)$serendipity['GET']['searchTerm']), double_encode: false);
+    $serendipity['GET']['searchTerm'] = serendipity_specialchars(strip_tags((string)$serendipity['GET']['searchTerm']), null, LANG_CHARSET, false);
 }
 
 // Some default inits...