Intent of schedule_to_start_timeout_not_set

All 2 exact tests in this concept. Every test is marked by where it enters the hierarchy.

go.temporal.io/ 2 tests
- server/ 2 tests
  - chasm/ 2 tests
    
    lib/ 2 tests
    
    activity/ 2 tests
    
    TestTransitionScheduled/ 2 tests
    
    go.temporal.io/server/chasm/lib/activity/TestTransitionScheduled/all_timeouts_set Inherited all_timeouts_set
    
    go.temporal.io/server/chasm/lib/activity/TestTransitionScheduled/schedule_to_start_timeout_not_set Introduced here