Copy edits (#35536)

* Copy edits to Basic JavaScript section

* Copy edits to ES6 section

* Update index.md

guide/english/certifications/javascript-algorithms-and-data-structures/es6/declare-a-read-only-variable-with-the-const-keyword/index.md

@@ -38,7 +38,7 @@ Change all the variables to `let` or `const` and rename `sentence`.
     function printManyTimes(str) {
       "use strict";
       const SENTENCE = str + " is cool!";
-      for(let i = 0; i < str.length; i+=2) {
+      for (let i = 0; i < str.length; i+=2) {
         console.log(SENTENCE);
       }
     }

guide/english/certifications/javascript-algorithms-and-data-structures/es6/prevent-object-mutation/index.md

@@ -31,7 +31,7 @@ _You need to freeze the `MATH_CONSTANTS` object so that no one is able to alter
       
       try {
         MATH_CONSTANTS.PI = 99;
-      } catch( ex ) {
+      } catch(ex) {
         console.log(ex);
       }
       return MATH_CONSTANTS.PI;

guide/english/certifications/javascript-algorithms-and-data-structures/es6/use-getters-and-setters-to-control-access-to-an-object/index.md

@@ -31,14 +31,14 @@ function makeClass() {
   "use strict";
   /* Alter code below this line */
   
-  class Thermostat{
-    constructor(fahrenheit){
+  class Thermostat {
+    constructor(fahrenheit) {
       this.fahrenheit = fahrenheit;
     }
-    get temperature(){
+    get temperature() {
       return 5 / 9 * (this.fahrenheit - 32);
     }
-    set temperature(celsius){
+    set temperature(celsius) {
       this.fahrenheit = celsius * 9.0 / 5 + 32;
     }
   }

guide/english/certifications/javascript-algorithms-and-data-structures/es6/write-higher-order-arrow-functions/index.md

@@ -35,7 +35,7 @@ We need to compute and square values from the `realNumberArray` and store them i
 ```javascript
     const squareList = (arr) => {
       "use strict";
-      const squaredIntegers = arr.filter( (num) => num > 0 && num % parseInt(num) === 0 ).map( (num) => Math.pow(num, 2) );
+      const squaredIntegers = arr.filter((num) => num > 0 && num % parseInt(num) === 0).map((num) => Math.pow(num, 2));
       return squaredIntegers;
     };