[Notif redesign] Update fonts in actions & smart replies

The font for smart replies and smart actions was already
google-sans-flex, I just updated them to use the correct font token so
that part is flagged behind the templates flag.

Bug: 378660052
Bug: 409496809
Test: manual + screenshot tests
Flag: android.app.notifications_redesign_templates
Flag: android.app.notifications_redesign_fonts
Change-Id: Iaa9a7a8371246ab9098a598b7e972f8b2fd86dae