expected output が実際の出力と match しない (#667)

[110, 220, 330, 440, 550] -> 120,240,360,480,600
document.write の出力形式に合わせ、浮動小数点誤差をなくすため taxRate を2倍した

Author: aster-void

docs/2-browser-apps/04-anonymous-function/index.mdx

@@ -81,11 +81,11 @@ const add3 = function (a, b) {
 
 ```javascript
 const pricesWithoutTax = [100, 200, 300, 400, 500];
-const taxRate = 0.1;
+const taxRate = 0.2;
 const pricesWithTax = pricesWithoutTax.map((price) => {
   return price * (1 + taxRate);
 });
-document.write(pricesWithTax); // [110, 220, 330, 440, 550]
+document.write(pricesWithTax); // 120,240,360,480,600
 ```
 
 :::tip[プリミティブ値のラッパーオブジェクト]