Improve detail link contrast in dark mode (#8548)
Use our light-mode styling for links in that context.
<img width="627" alt="Screen Shot 2023-11-07 at 4 34 48 PM"
src="https://github.com/astral-sh/ruff/assets/1309177/1e30c3ac-18e2-4663-876c-75c6f8b67d53">
Closes https://github.com/astral-sh/ruff/issues/8519.
