Intent of New_sets_only_the_current_time

All 5 exact tests in this concept. Every test is marked by where it enters the hierarchy.

go.temporal.io/ 5 tests
- server/ 5 tests
  - service/ 5 tests
    
    history/ 5 tests
    
    workflow/ 5 tests
    
    TestTimeSkippingTransition/ 5 tests
    
    fast-forward_fallback_and_gating/ 3 tests
    
    go.temporal.io/server/service/history/workflow/TestTimeSkippingTransition/fast-forward_fallback_and_gating/past_target_disables_as_a_bare_signal Inherited past_target_disables_as_a_bare_signal
    
    go.temporal.io/server/service/history/workflow/TestTimeSkippingTransition/fast-forward_fallback_and_gating/taken_as_the_target_and_disables_when_nothing_earlier_exists Inherited target_equal_to_current_disables_and_sets_the_target, taken_as_the_target_and_disables_when_nothing_earlier_exists
    
    go.temporal.io/server/service/history/workflow/TestTimeSkippingTransition/fast-forward_fallback_and_gating/target_equal_to_current_disables_and_sets_the_target Inherited target_equal_to_current_disables_and_sets_the_target, taken_as_the_target_and_disables_when_nothing_earlier_exists
    
    go.temporal.io/server/service/history/workflow/TestTimeSkippingTransition/New_sets_only_the_current_time Introduced here
    
    go.temporal.io/server/service/history/workflow/TestTimeSkippingTransition/nil_safe Inherited nil_safe