fix: fix typos in tests of css selectors builder subtask

[asfound]

Title of Pull Request

Fix typos in tests of css selectors builder subtask

🤔 This is a ...

• 🌟 New task
• 🌐 New module
• ⚙️ Update to an existing task
• 🔧 Update to an existing module
• 🔗 Update or addition of external resources or links
• 🐛 Fix in a task or related content
• 🛠 Fix in a module or related content
• ✏️ Fixed a typo or grammatical error
• 🔗 Fixed a broken link
• ❓ Other (specify: ****____****)

Description

• Brief Overview:
  Clarified the spelling of the verb 'create' after 'should'. Corrected 'then' to 'than' to align with the intended meaning of the exception text, ensuring consistency with the rule that an element, ID, or pseudo-element should not occur more than once inside the selector.

Additional Information

• Screenshots/Links:
• Related Issues:

Checklist

• ✅ I have performed a self-review of my own code.
• 📝 I have commented my code, particularly in hard-to-understand areas.
• 🔧 I have made corresponding changes to the documentation (if applicable).
• 🚫 My changes generate no new warnings or errors.