update to solid-client-authn-browser > 15 (deprecation notice)

https://github.com/inrupt/solid-client-authn-js/blob/main/CHANGELOG.md#deprecation-notice
> Session methods `onLogin,` `onLogout,` `onError,` `onSessionRestore,` `onSessionExpiration,` `onNewRefreshToken` are deprecated in favor of session.events.on called with the appropriate event name.

Changes should be located mainly in https://github.com/SolidOS/solid-ui/blob/main/src/login/login.ts