Open ETP Server crashes with PostgreSQLException (intermittent)

How to reproduce: Enable multi-thread benchmark Client_ConnectionPingMt (to be added in !123 (merged)), there are ToDo comment in the file:

src/benchmark/client/ClientConnectionBenchmark.cpp

Build and run oesBenchmark.

Expected result: All benchmarks should successfully pass

Actual result: Crashes with PostgreSQLException

Please pay attention that Client_ConnectionPingMt is like trigger for appear the bug, if run each benchmark separately, they will successfully pass.