Minor tweaks to repo topics: - Use gap instead of margin to align "Manage Topics" when no topics present - Add margin to description instead Before: <img width="1232" alt="Screenshot 2023-07-08 at 13 08 15" src="https://github.com/go-gitea/gitea/assets/115237/a5d3586c-6cbf-4b74-8137-11d91f2cbb45"> <img width="1233" alt="Screenshot 2023-07-08 at 13 08 05" src="https://github.com/go-gitea/gitea/assets/115237/59b18d93-e4cb-4f2b-9bc2-d6aa63f93827"> After: <img width="1232" alt="Screenshot 2023-07-08 at 13 08 42" src="https://github.com/go-gitea/gitea/assets/115237/470d42ad-3f7e-40f9-b0a1-203b4af77eb9"> <img width="1231" alt="Screenshot 2023-07-08 at 13 08 32" src="https://github.com/go-gitea/gitea/assets/115237/42d18048-748c-4a3f-ab89-3403866cef34"> ---------
