This PR makes it so the `/fetch` slash command will display an error when the URL does not have any textual content: <img width="308" alt="Screenshot 2024-08-08 at 4 51 55 PM" src="https://github.com/user-attachments/assets/bf4cbc18-c65b-48a2-aedd-26b50f47f018"> Release Notes: - N/A