Don't crash node in the case of duplicate tag. (#11370)

Author: Tony-Romanov

ydb/core/load_test/service_actor.cpp

@@ -432,17 +432,17 @@ class TLoadActor : public TActorBootstrapped<TLoadActor> {
     }
 
     void Handle(TEvLoad::TEvLoadTestRequest::TPtr& ev) {
-        ui32 status = NMsgBusProxy::MSTATUS_OK;
-        TString error;
         const auto& record = GetFixedRequest(ev);
-        Y_ENSURE(!RequestSender.contains(record.GetTag()),
-            "node is currently handling another request with tag# " << record.GetTag());
-        RequestSender[record.GetTag()] = ev->Sender;
-        UuidByTag[record.GetTag()] = record.GetUuid();
         LOG_N("Load test request arrived from " << ev->Sender.ToString() <<
             ": tag# " << record.GetTag() <<
             ", uuid# " << record.GetUuid());
+        ui32 status = NMsgBusProxy::MSTATUS_OK;
+        TString error;
         try {
+            Y_ENSURE(!RequestSender.contains(record.GetTag()),
+                "node is currently handling another request with tag# " << record.GetTag());
+            RequestSender[record.GetTag()] = ev->Sender;
+            UuidByTag[record.GetTag()] = record.GetUuid();
             ProcessCmd(record);
         } catch (const TLoadActorException& ex) {
             LOG_E("Exception while creating load actor, what# " << ex.what());
@@ -1060,7 +1060,7 @@ class TLoadActor : public TActorBootstrapped<TLoadActor> {
                             if (result.status == "ok") {
                                 updateStatus(
                                     "text-success",
-                                    "Started: UUID# " + result.uuid + ", node tag# " + result.tag + ", status# " + result.status
+                                    "Starting: UUID# " + result.uuid + ", node tag# " + result.tag + ", status# " + result.status
                                 );
                             } else {
                                 updateStatus(