Fix typo.

Author: afoucret

src/framework-app-search/Document/SyncManager.php

@@ -206,7 +206,7 @@ private function waitForSync(string $engineName, int $expectedCount)
                     usleep(200);
                 }
                 $resp = $this->client->search($engineName, '', $searchParams);
-                $attempts --;
+                $attempts--;
             } while ($attempts > 0 && $resp['meta']['page']['total_results'] < $expectedCount);
         }
     }