Rustfmt misaligns doc comment between rustfmt::skip modules

mod modules {
    #[rustfmt::skip]
    #[path = "/dev/null"]
    mod first;

    /// ...
    /// ...
    #[rustfmt::skip]
    #[path = "/dev/null"]
    mod second;
}

Running rustfmt on this file turns it into:

mod modules {
    #[rustfmt::skip]
    #[path = "/dev/null"]
    mod first; /// ...
               /// ...
    #[rustfmt::skip]
    #[path = "/dev/null"]
    mod second;
}

<     mod first;
<
<     /// ...
<     /// ...
---
>     mod first; /// ...
>                /// ...

Observations:

• The #[path = "/dev/null"] attribute is not necessary for the repro. It is just to make this reproducible with a single input file.
• Both #[rustfmt::skip] are necessary for the repro. Without either one, the problem does not occur.
• Both ; are necessary for the repro. If either module uses {​} instead of ;, the problem does not occur.
• The outer module is necessary.

Start by running rustfmt on the single-file Rust example in the issue and confirm the doc comments move onto the first skipped module. Trace rustfmt's handling of consecutive #[rustfmt::skip] modules and their doc comments. Done means formatting preserves the comments as separate lines before the second module without changing the surrounding code.