EventBookkeeperTPCnv: Tweak leak-checking for gcc10.

Need to	call currentContext() before starting leakcheck.

Event/EventBookkeeperTPCnv/test/EventBookkeeperCnv_p1_test.cxx

 /*
-  Copyright (C) 2002-2019 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
-
-// $Id$
 /**
  * @file EventBookkeeperTPCnv/test/EventBookkeeperCnv_p1_test.cxx
  * @author scott snyder <snyder@bnl.gov>
@@ -15,6 +13,7 @@
 #include "EventBookkeeperTPCnv/EventBookkeeperCnv_p1.h"
 #include "CxxUtils/StrFormat.h"
 #include "TestTools/leakcheck.h"
+#include "GaudiKernel/ThreadLocalContext.h"
 #include <cassert>
 #include <iostream>
 
@@ -76,6 +75,7 @@ std::unique_ptr<EventBookkeeper> make (int o)
 void test1()
 {
   std::cout << "test1\n";
+  (void)Gaudi::Hive::currentContext();
   Athena_test::Leakcheck check;
 
   std::unique_ptr<EventBookkeeper> trans1 = make(1);