Adds initial intermediate qt6 porting state

qt6-after/qt6-migrated-legatus/Lts/DDS/DdsUnitTestsPlaceholder/ddsFunctionTopicTests_smoke.cpp

@@ -0,0 +1,22 @@
+#include <QObject>
+#include <QtTest>
+
+class FunctionTopicSmokeTest : public QObject {
+  Q_OBJECT
+private slots:
+  void test_containers() {
+    QStringList list;
+    list << QStringLiteral("a") << QStringLiteral("b") << QStringLiteral("c");
+    QCOMPARE(list.size(), 3);
+    QVERIFY(list.contains(QStringLiteral("b")));
+  }
+  void test_qmap_basic() {
+    QMap<QString,int> m;
+    m[QStringLiteral("one")] = 1;
+    m[QStringLiteral("two")] = 2;
+    QCOMPARE(m.value(QStringLiteral("two")), 2);
+  }
+};
+
+QTEST_MAIN(FunctionTopicSmokeTest)
+#include "ddsFunctionTopicTests_smoke.moc"