Fix stripe#238 two receipts sent for subscriptions

CRM/Core/Payment/MJWIPNTrait.php

@@ -233,7 +233,8 @@ trait CRM_Core_Payment_MJWIPNTrait {
 
     // Create the new contribution
     $contributionParams['trxn_id'] = $params['order_reference'];
-    $contributionParams['is_email_receipt'] = $this->getSendEmailReceipt();
+    // We send a receipt when adding a payment, not now
+    $contributionParams['is_email_receipt'] = FALSE;
     $contribution = civicrm_api3('Contribution', 'repeattransaction', $contributionParams);
 
     if ($createPayment) {