Intent of signal_workflows, signal_(legacy_enum)

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
  - service/ 2 tests
    
    frontend/ 2 tests
    
    TestBatchOperationTypeMemoRoundTrip/ 2 tests
    
    go.temporal.io/server/service/frontend/TestBatchOperationTypeMemoRoundTrip/signal_(legacy_enum) Introduced here
    
    go.temporal.io/server/service/frontend/TestBatchOperationTypeMemoRoundTrip/signal_workflows Introduced here