message: Further test stability improvement
diff: @@ -240,12 +240,15 @@ BOOST_FIXTURE_TEST_CASE(dip3_activation, TestChainDIP3BeforeActivationSetup)
  // This block should activate DIP3
  CreateAndProcessBlock({}, coinbaseKey);
  + LOCK(cs_main);
  BOOST_ASSERT(chainActive.Height() == nHeight + 1);
  // Mining a block with a DIP3 transaction should succeed now
  block = std::make_shared<CBlock>(CreateBlock(txns, coinbaseKey));
  ProcessNewBlock(Params(), block, true, nullptr);
  deterministicMNManager->UpdatedBlockTip(chainActive.Tip());
  +
  + LOCK(cs_main);
  BOOST_ASSERT(chainActive.Height() == nHeight + 2);
  BOOST_ASSERT(block->GetHash() == chainActive.Tip()->GetBlockHash());
  BOOST_ASSERT(deterministicMNManager->GetListAtChainTip().HasMN(tx.GetHash()));
  