Close curl handle after removing them from curl-multi-handle (#109)

Author: staabm

src/utils/HttpClient.php

@@ -69,6 +69,7 @@ public function getMulti(array $urls, array $headers): array
             $result[$url] = [$responseCode, $response];
 
             curl_multi_remove_handle($mh, $handle);
+            curl_close($handle);
         }
         curl_multi_close($mh);