Cannot build the doc on Sphinx 9.1.0 #200

      File "/home/user/src/h11/docs/source/conf.py", line 61, in setup
        app.add_javascript("show-code.js")
        ^^^^^^^^^^^^^^^^^^
    AttributeError: 'Sphinx' object has no attribute 'add_javascript'

    diff --git a/docs/source/conf.py b/docs/source/conf.py
    index b3627f5..8eb6864 100644
    --- a/docs/source/conf.py
    +++ b/docs/source/conf.py
    @@ -58,9 +58,9 @@ extensions = [
     # Undocumented trick: if we def setup here in conf.py, it gets called just
     # like an extension's setup function.
     def setup(app):
    -    app.add_javascript("show-code.js")
    -    app.add_javascript("facebox.js")
    -    app.add_stylesheet("facebox.css")
    +    app.add_js_file("show-code.js")
    +    app.add_js_file("facebox.js")
    +    app.add_css_file("facebox.css")

     # Add any paths that contain templates here, relative to this directory.
     templates_path = ['_templates']