Fix expr-test

One of the tests in the expr-tests be unit tests starts a statestore, which causes the test to fail

./be/build/debug/runtime/data-stream-test
[==========] Running 4 tests from 1 test case.
[ RUN ] DataStreamTest.UnknownSenderLargeResult
F0707 13:52:47.863056 25192 lock-tracker.cc:32] Check failed: global_ == __null

• • • Check failure stack trace: ***
      @ 0x2336e4e google::LogMessage::Fail()
      @ 0x2336d98 google::LogMessage::SendToLog()
      @ 0x2336768 google::LogMessage::Flush()
      @ 0x2339705 google::LogMessageFatal::~LogMessageFatal()
      @ 0x1604dd7 impala::LockTracker::LockTracker()
      @ 0x13bc3e4 impala::ExecEnv::ExecEnv()
      @ 0x10d53cc impala::DataStreamTest::DataStreamTest()
      @ 0x10da670 impala::DataStreamTest_UnknownSenderLargeResult_Test::DataStreamTest_UnknownSenderLargeResult_Test()
      @ 0x10f9bc8 testing::internal::TestFactoryImpl<>::CreateTest()
      @ 0x23de223 testing::internal::HandleExceptionsInMethodIfSupported<>()
      @ 0x23d5a73 testing::TestInfo::Run()
      @ 0x23d5bd5 testing::TestCase::Run()
      @ 0x23d6e58 testing::internal::UnitTestImpl::RunAllTests()
      @ 0x23d7133 testing::UnitTest::Run()
      @ 0x10cc662 main
      @ 0x7ff8f48b0ec5 (unknown)
      @ 0x10cba85 (unknown)
      Aborted (core dumped)