Add reference to Google OAuth docs (#61048)

docs/sources/setup-grafana/configure-security/configure-authentication/google/index.md

@@ -39,6 +39,7 @@ auth_url = https://accounts.google.com/o/oauth2/auth
 token_url = https://accounts.google.com/o/oauth2/token
 allowed_domains = mycompany.com mycompany.org
 allow_sign_up = true
+hosted_domain = mycompany.com
 ```
 
 You may have to set the `root_url` option of `[server]` for the callback URL to be
@@ -53,6 +54,9 @@ You may allow users to sign-up via Google authentication by setting the
 user successfully authenticating via Google authentication will be
 automatically signed up.
 
+You may specify a domain to be passed as `hd` query parameter accepted by Google's
+OAuth 2.0 authentication API. Refer to Google's OAuth [documentation](https://developers.google.com/identity/openid-connect/openid-connect#hd-param).
+
 ### Configure refresh token
 
 > Available in Grafana v9.3 and later versions.