Turn on frontend.enableTokenNamespaceEnforcement by default (#3798)

Author: dnr

service/frontend/service.go

@@ -212,7 +212,7 @@ func NewConfig(dc *dynamicconfig.Collection, numHistoryShards int32, esIndexName
 		DefaultWorkflowRetryPolicy:             dc.GetMapPropertyFnWithNamespaceFilter(dynamicconfig.DefaultWorkflowRetryPolicy, common.GetDefaultRetryPolicyConfigOptions()),
 		DefaultWorkflowTaskTimeout:             dc.GetDurationPropertyFilteredByNamespace(dynamicconfig.DefaultWorkflowTaskTimeout, common.DefaultWorkflowTaskTimeout),
 		EnableServerVersionCheck:               dc.GetBoolProperty(dynamicconfig.EnableServerVersionCheck, os.Getenv("TEMPORAL_VERSION_CHECK_DISABLED") == ""),
-		EnableTokenNamespaceEnforcement:        dc.GetBoolProperty(dynamicconfig.EnableTokenNamespaceEnforcement, false),
+		EnableTokenNamespaceEnforcement:        dc.GetBoolProperty(dynamicconfig.EnableTokenNamespaceEnforcement, true),
 		KeepAliveMinTime:                       dc.GetDurationProperty(dynamicconfig.KeepAliveMinTime, 10*time.Second),
 		KeepAlivePermitWithoutStream:           dc.GetBoolProperty(dynamicconfig.KeepAlivePermitWithoutStream, true),
 		KeepAliveMaxConnectionIdle:             dc.GetDurationProperty(dynamicconfig.KeepAliveMaxConnectionIdle, 2*time.Minute),