Add openid-connecter discovery route

src/main.rs

@@ -123,6 +123,9 @@ async fn main() -> std::io::Result<()> {
             // Admin API
             .route("/admin/api/find_username", web::post().to(admin_api::find_username))
             .route("/admin/api/delete_user", web::post().to(admin_api::delete_user))
+
+            // OpenID specs
+            .route(".well-known/openid-configuration", web::get().to(openid_controller::get_configuration))
     })
         .bind(listen_address)?
         .run()