Intent of SignalExternalWorkflow

All 3 exact tests in this concept. Every test is marked by where it enters the hierarchy.

go.temporal.io/ 3 tests
- server/ 3 tests
  - common/ 3 tests
    
    authorization/ 3 tests
    
    TestAuthorizerInterceptorSuite/ 3 tests
    
    TestCrossNamespaceCommands_Authorized/ 1 test
    
    go.temporal.io/server/common/authorization/TestAuthorizerInterceptorSuite/TestCrossNamespaceCommands_Authorized/SignalExternalWorkflow Introduced here
    
    go.temporal.io/server/common/authorization/TestAuthorizerInterceptorSuite/TestMultipleCommands_AuthDeduplication Inherited interceptor.go ×1
    
    go.temporal.io/server/common/authorization/TestAuthorizerInterceptorSuite/TestMultipleTargetNamespaces Inherited TestMultipleTargetNamespaces