Change icon for tram stops from bus

[starsep]

Currently bus icon is displayed also for tram stops. I think that's confusing.
For tram stops I would expect tram icon.
I am not sure how to handle shared bus/tram stops

Example tram stop Plac Konstytucji 05
Stop: https://osm.org/node/1412975402
Platform: https://osm.org/node/10931504175

They both have tram=yes tag.

I think the relevant code is here: https://github.com/Zaczero/osm-relatify/blob/7ad146867f71549d510eeeeca725558c1a1ff306/web/static/js/busStopsLayer.js

cc @goteusz-maszyk