msalConfig auth authority URL

It is not working if the authority URL in `authConfig.js` (`ms-identity-ciam-javascript-tutorial\1-Authentication\0-sign-in-vanillajs\App\public\authConfig.js`) is `https://.ciamlogin.com/`, but it works with `https://.ciamlogin.com//v2.0`

```js
const msalConfig = {
auth: {
clientId: 'Enter_the_Application_Id_Here', // This is the ONLY mandatory field that you need to supply.
authority: 'https://Enter_the_Tenant_Subdomain_Here.ciamlogin.com/Enter_the_Tenant_Subdomain_Here/v2.0', // Replace the placeholders with your tenant subdomain
redirectUri: 'http://localhost:3000/redirect', // You must register this URI on Microsoft Entra admin center/App Registration. Defaults to window.location.href e.g. http://localhost:3000/
navigateToLoginRequestUrl: true, // If "true", will navigate back to the original request location before processing the auth code response.
},
...
}
```

Start with ms-identity-ciam-javascript-tutorial\1-Authentication\0-sign-in-vanillajs\App\public\authConfig.js and reproduce the sign-in flow with each authority URL shown in the issue. Compare the resulting behavior and confirm the expected authority format for this tutorial configuration.

Written by the indexing model from the issue text.