use strpos instead of str_contains for php 7 compatibility

Author: stijnvandervegt

Service/MethodService.php

@@ -204,6 +204,6 @@ private function createCmOrder(CartInterface $quote): OrderCreate
      */
     private function isCmPaymentsMethod(string $paymentMethodCode): bool
     {
-        return str_contains($paymentMethodCode, ConfigProvider::CODE . '_');
+        return strpos($paymentMethodCode, ConfigProvider::CODE . '_') !== false;
     }
 }