Add configuration for client sso using native browser

manual/config/seahub_settings_py.md

@@ -310,6 +310,7 @@ ENABLE_SHIBBOLETH_LOGIN = True
 # Enable client to open an external browser for single sign on
 # When it is false, the old buitin browser is opened for single sign on
 # When it is true, the default browser of the operation system is opened
+# The benefit of using system browser is that it can support hardware 2FA
 # Since 11.0.0, and sync client 9.0.5, drive client 3.0.8
 CLIENT_SSO_VIA_LOCAL_BROWSER = True   # default is False
 CLIENT_SSO_UUID_EXPIRATION = 5 * 60