Fix persistent local flag in session url updating (#13905)

Short-lived regression from 5ce9687.
I forgot to add the persistent local flag, so that means that RC_DEBUG
will complain. These strings are local to the thread so we can just add
the flag to silence the debug checker in this case.

Author: nielsdos

ext/standard/url_scanner_ex.re

@@ -140,6 +140,7 @@ static int php_ini_on_update_hosts(zend_ini_entry *entry, zend_string *new_value
 		if (keylen > 0) {
 			/* Note: the hash table is persistently allocated, so the strings must be too! */
 			tmp_key = zend_string_init(key, keylen, true);
+			GC_MAKE_PERSISTENT_LOCAL(tmp_key);
 			zend_hash_add_empty_element(hosts, tmp_key);
 			zend_string_release_ex(tmp_key, true);
 		}