_solara/cdn is broken in jupyter notebook classic

[iisakkirotko]

Seems to be because of jupyter server. Tested (and fails) with

solara: development install, ~1.38.0
notebook: 6.4.13 - 6.5.7
server: 2.13.0 - 2.14.2

Works with jupyter_server<2

The error we get is:

GET http://localhost:8889/_solara/cdn/mermaid@10.8.0/dist/mermaid.min.js?v=20240830132155 net::ERR_TOO_MANY_REDIRECTS

We suspect this is caused by the need for authentication in jupyter server, see this warning here

    @property
    def authorizer(self) -> Authorizer:
        if "authorizer" not in self.settings:
            warnings.warn(
                "The Tornado web application does not have an 'authorizer' defined "
                "in its settings. In future releases of jupyter_server, this will "
                "be a required key for all subclasses of `JupyterHandler`. For an "
                "example, see the jupyter_server source code for how to "
                "add an authorizer to the tornado settings: "
                "https://github.com/jupyter-server/jupyter_server/blob/"
                "653740cbad7ce0c8a8752ce83e4d3c2c754b13cb/jupyter_server/serverapp.py"
                "#L234-L256",
                stacklevel=2,
            )
            from jupyter_server.auth import AllowAllAuthorizer

            self.settings["authorizer"] = AllowAllAuthorizer(
                config=self.settings.get("config", None),
                identity_provider=self.identity_provider,
            )

        return cast("Authorizer", self.settings.get("authorizer"))

This is how they advice for it to be implemented:

        if identity_provider is None:
            warnings.warn(
                "identity_provider unspecified. Using default IdentityProvider."
                " Specify an identity_provider to avoid this message.",
                RuntimeWarning,
                stacklevel=2,
            )
            identity_provider = IdentityProvider(parent=jupyter_app)