WikiArtifact instances also have provides; limit ivy to jvm

This should never get hit unless you accidentally do goal compile on a
wiki -- but maybe you do compile ...:: and hit it.

Testing Done:
Ran tests.

Reviewed at https://rbcommons.com/s/twitter/r/1259/
Sync of https://github.com/pantsbuild/pants/commit/aa631e347d0c2a424f13dd792a299a1937a03196