fix CI

Author: LamentXU123

ext/soap/tests/soap_array_index_overflow.phpt

@@ -4,6 +4,8 @@ SOAP array index overflow is rejected
 soap
 --FILE--
 <?php
+class TestSoapClient extends SoapClient {
+    public string $response;
 
     public function __doRequest($request, $location, $action, $version, $one_way = false, ?string $uriParserClass = null): string {
         return $this->response;