Locking around build_requested for race condition (AUE-382)

Lock around build requested to avoid a scenario where builds that are requested are not made.

Would especially like input from @nnutter and @tmooney
Keep in mind that `GENOME_SOFTWARE_RESULT_TEST_NAME` is abused and is always set for CLE.  If `GENOME_SOFTWARE_RESULT_TEST_NAME` was trying to avoid the problem of multiple tests models running simultaneously then I think we need a different solution.  The first thing that comes to mind is maybe we should set `GENOME_LOCK_DIR` in the model tests.