Intent of TestEventStore_RolloverOnSizeThreshold, TestEventStore_SingleOversizedEventAppended

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
    
    history/ 2 tests
    
    historybuilder/ 2 tests
    
    TestHistoryBuilderSuite/ 2 tests
    
    go.temporal.io/server/service/history/historybuilder/TestHistoryBuilderSuite/TestEventStore_RolloverOnSizeThreshold Introduced here
    
    go.temporal.io/server/service/history/historybuilder/TestHistoryBuilderSuite/TestEventStore_SingleOversizedEventAppended Introduced here