Rollup merge of #117869 - GuillaumeGomez:comment-highlighting-item-decl, r=notriddle

[rustdoc] Add highlighting for comments in items declaration

Fixes #117555.

So after the discussion in https://github.com/rust-lang/rust/pull/117643, the outcome was that having the comments in the item declaration at the same level (in term of color) as the rest of the code was actually a bit distracting and could be improved.

The current highlighting color for comments is "lighter" than the rest and I think it fits perfectly to improve the current situation. With this, we now have different "levels" which makes it easier to read and filter out what we want when reading the items declaration.

Here's a screenshot:

![image](https://github.com/rust-lang/rust/assets/3050060/dbd98029-e98b-4997-9a89-6b823eaac9a4)

r? `@notriddle`

0 files changed, 0 insertions, 0 deletions