Function check 

pub fn check(
    root_path: &Path,
    outdir: &Path,
    ci_info: &CiInfo,
    librustdoc_path: &Path,
    tools_path: &Path,
    npm: &Path,
    cargo: &Path,
    bless: bool,
    extra_checks: Option<&str>,
    pos_args: &[String],
    diag_ctx: DiagCtx,
)