feat(curriculum): add log with function call to challenge (#44195)

* fix (Curriculum) Added a log statement

Added a log statement to the seed's content, referencing the function countOnline with a sample object as argument.
The user should be able to see the result of the function printed out on the console as soon as it is ran, and it should be easier to understand what is being outputed by the function in this challenge.

* Added examper users object

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/iterate-through-the-keys-of-an-object-with-a-for...in-statement.md

@@ -116,11 +116,25 @@ const usersObj3 = {
 ## --seed-contents--
 
 ```js
+const users = {
+  Alan: {
+    online: false
+  },
+  Jeff: {
+    online: true
+  },
+  Sarah: {
+    online: false
+  }
+}
+
 function countOnline(usersObj) {
   // Only change code below this line
 
   // Only change code above this line
 }
+
+console.log(countOnline(users));
 ```
 
 # --solutions--