use round instead of number_format to round the total amount

Author: jayankaghosh

app/code/Magento/Quote/Model/Quote/Address/Total.php

@@ -56,7 +56,7 @@ public function __construct(
     public function setTotalAmount($code, $amount)
     {
         /* (Fixes issue #18027) Round the total amount to 4 decimal places, to avoid floating point overflows */
-        $amount = is_float($amount) ? (float)number_format($amount, 4, ".", "") : $amount;
+        $amount = is_float($amount) ? round($amount, 4) : $amount;
 
         $this->totalAmounts[$code] = $amount;
         if ($code != 'subtotal') {
@@ -77,7 +77,7 @@ public function setTotalAmount($code, $amount)
     public function setBaseTotalAmount($code, $amount)
     {
         /* (Fixes issue #18027) Round the total amount to 4 decimal places, to avoid floating point overflows */
-        $amount = is_float($amount) ? (float)number_format($amount, 4, ".", "") : $amount;
+        $amount = is_float($amount) ? round($amount, 4) : $amount;
 
         $this->baseTotalAmounts[$code] = $amount;
         if ($code != 'subtotal') {