[HttpClient] fix HttpClientDataCollector when handling canceled responses

Author: thematchless

DataCollector/HttpClientDataCollector.php

@@ -120,7 +120,7 @@ private function collectOnClient(TraceableHttpClient $client): array
                 unset($info['http_method']);
             }
 
-            if ($trace['url'] === $info['url']) {
+            if (($info['url'] ?? null) === $trace['url']) {
                 unset($info['url']);
             }