Change name of `np_uni_schedule`

This name is a bit problematic. From np_uni_schedule, one may assume non preemptive uniprocessor schedule.

np_aware_uni_schedule, preemption_aware_uni_schedule, and pmc_uni_schedule have been poposed

mentioned in merge request !209 (merged)

closed with commit b5e717e6

mentioned in commit b5e717e6