kiji-end-to-end-tests: EXP-309. Add kiji-express-music and to the end-to-end test.

issue: https://jira.kiji.org/browse/EXP-309
review: https://review.kiji.org/r/1592
commit: https://github.com/kijiproject/kiji-end-to-end-tests/commit/75d6dd69077d75ba3f15b44dbcaf25583c56d513