The included directory is not registered as a build dependency

[maurges]

Here's a minimal example:

fn main() {
    static FILES: include_dir::Dir =
        include_dir::include_dir!("$CARGO_MANIFEST_DIR/files");
    for file in FILES.entries().iter() {
        println!("{:?} {:?}", file.path(), file.as_file().map(|f| f.contents_utf8()))
    }
}

I then mkdir files and add a couple of files:

> echo foo > files/foo
> echo bar > files/bar

After the first build, the files are shown as expected:

> cargo run
"bar" Some(Some("bar\n"))
"foo" Some(Some("foo\n"))

Modifying the file will recompile as expected:

> echo 'not bar' > files/bar && cargo run
"bar" Some(Some("not bar\n"))
"foo" Some(Some("foo\n"))

But adding a new file will not recompile:

> echo 'kek' > files/kek && cargo run
"bar" Some(Some("not bar\n"))
"foo" Some(Some("foo\n"))