Intent of returns_true_for_MultiOperationExecution_with_ErrWorkflowClosing, handles_MultiOperationExecution_with_mix_of_nil_and_retryable_errors

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
    
    worker/ 2 tests
    
    workerdeployment/ 2 tests
    
    TestIsRetryableUpdateError/ 2 tests
    
    go.temporal.io/server/service/worker/workerdeployment/TestIsRetryableUpdateError/handles_MultiOperationExecution_with_mix_of_nil_and_retryable_errors Introduced here
    
    go.temporal.io/server/service/worker/workerdeployment/TestIsRetryableUpdateError/returns_true_for_MultiOperationExecution_with_ErrWorkflowClosing Introduced here