fix(curriculum): add test cases to ensure single whitespace (#49417)

* fix: update solutions regex to reflect test cases

---------

Co-authored-by: javrrr <javrrr@gmail>

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/reuse-patterns-using-capture-groups.md

@@ -96,6 +96,20 @@ reRegex.lastIndex = 0;
 assert(reRegex.test('10 10 10'));
 ```
 
+Your regex should not match the string `42\t42\t42`.
+
+```js
+reRegex.lastIndex = 0;
+assert(!reRegex.test('42\t42\t42'));
+```
+
+Your regex should not match the string `42  42  42`.
+
+```js
+reRegex.lastIndex = 0;
+assert(!reRegex.test('42  42  42'));
+```
+
 # --seed--
 
 ## --seed-contents--
@@ -110,6 +124,6 @@ let result = reRegex.test(repeatNum);
 
 ```js
 let repeatNum = "42 42 42";
-let reRegex = /^(\d+)\s\1\s\1$/;
+let reRegex = /^(\d+) \1 \1$/;
 let result = reRegex.test(repeatNum);
 ```