fix thread sanitizer alert (#13578)

Author: ivanmorozov333

ydb/core/tx/columnshard/engines/reader/common_reader/iterator/fetching.cpp

@@ -120,7 +120,7 @@ void TFetchingScript::Allocation(const std::set<ui32>& entityIds, const EStageFe
 
 TString IFetchingStep::DebugString() const {
     TStringBuilder sb;
-    sb << "name=" << Name << ";duration=" << SumDuration << ";"
+    sb << "name=" << Name << ";duration=" << GetSumDuration() << ";"
        << "size=" << 1e-9 * SumSize << ";details={" << DoDebugString() << "};";
     return sb;
 }

ydb/core/tx/columnshard/engines/reader/common_reader/iterator/fetching.h

@@ -67,7 +67,7 @@ class TFetchingStepsSignalsCollection: public NColumnShard::TCommonCountersOwner
 class IFetchingStep: public TNonCopyable {
 private:
     YDB_READONLY_DEF(TString, Name);
-    YDB_READONLY(TDuration, SumDuration, TDuration::Zero());
+    TAtomicCounter SumDuration;
     YDB_READONLY(ui64, SumSize, 0);
     TFetchingStepSignals Signals;
 
@@ -78,8 +78,12 @@ class IFetchingStep: public TNonCopyable {
     }
 
 public:
+    TDuration GetSumDuration() const {
+        return TDuration::MicroSeconds(SumDuration.Val());
+    }
+
     void AddDuration(const TDuration d) {
-        SumDuration += d;
+        SumDuration.Add(d.MicroSeconds());
         Signals.AddDuration(d);
     }
     void AddDataSize(const ui64 size) {