[upstream_utils] Remove ConcurrentQueue (#7183)

It appears to be broken under stress testing (dropped/duplicate values).

This reverts commit 97c6c86f3b (#7066).

wpiutil/src/test/native/cpp/concurrentqueue/ConcurrentQueueTest.cpp

@@ -1,17 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include <gtest/gtest.h>
-
-#include "wpi/concurrentqueue.h"
-
-TEST(ConcurrentQueueTest, Basic) {
-  wpi::ConcurrentQueue<int> q;
-  q.enqueue(25);
-
-  int item;
-  bool found = q.try_dequeue(item);
-  EXPECT_TRUE(found);
-  EXPECT_EQ(item, 25);
-}