StaticLinkageChecker for classpath for each artifact

Note from the discussion with @patflynn . (Not decided how to implement it yet)

As of now, the dashboard has a (global) static linkage check result. This idea is to run StaticLinkageChecker against each classpath of the Maven artifacts in a BOM to get artifact-level result.

This corresponds the relationship between "global upper bounds" and "(local) upper bounds".

If there is a static linkage conflict in a class path from Maven artifact's dependencies, it's a simpler problem than the one against a big class path from BOM.