Add new reviewer to librustdoc static files

[Folyd]

Ping @Folyd if some changes occurred in librustdoc's HTML/CSS/JS.

Related context: rust-lang/rust#91062 (comment)

[jyn514]

@Mark-Simulacrum could you merge this please?

[Mark-Simulacrum]

I am not sure we want to add external folks to the ping lists here -- it implies a level of officialness, and for example the target tier policy talks about not pinging and such for relatively similar reasons.

So my initial inclination is to suggest that this is likely not quite the right path to doing this, even though it looks like a trivial change. It might be useful to have a discussion amongst the rustdoc team as to whether this is the expected way of dealing with changes here -- I recall that other parts of rustdoc, like the JSON API crate, are explicitly versioned (which may imply an opportunity for changelogs / blog posts / something on bumps).

[jyn514]

I really don't want any part of the CSS to be a stable API. The alternative to this is for @Folyd to keep only finding breaking changes after they occur; I think it's reasonable to ping them ahead of time without implying that the PR needs to change. My understanding is that the target policy is saying team members shouldn't be pinged for breakage to tier 3 targets; I don't think it's unreasonable for the target maintainers to be pinged.

[Mark-Simulacrum]

I'm okay adding this since we're already putting in the comments (i.e., it's not a new comment that gets generated), so the added noise is minimal, but I think we may want to reconsider if the list grows.