Investigate whether it is possible to override add-on components spring configuration in projects assembly overrides

This is related to HSTTWO-2038

The improvements from there work very well, and you can hook in spring component managed behavior from addon jars without the need to add any spring configuration in a custom project hst-assembly overrides.

However, it would be nice, if you could still override an addon spring component id. I am not sure if this is possible. However, assume the following use case:

For some addon jar X, shipping with some addon spring component, we can choose between multiple different implementations (database stored, session store, clustered in memory store, etc). It would be nice, if the end project could still set in this example which store to be used.

I am not sure how this could be done. Obviously, we could create three different addon jars (X-databasestored, X-sessionstore, X-inmemory) containing three different addon spring components, but I think this is undesirable.