qmltc: Test failure on presence of non-top level required property

`qmltc` should fail when it processes a QML file that has a required
property that is not top-level, as it is invalid QML.

For example:

```
import QtQuick

Item {
  Item {
    required property int foo
  }
}
```

To parse a QML file, `qmltc` uses `QQmlJSImportVisitor`, which will
produce an error on encountering such a property.

`qmltc` will in turn propagate the error and fail itself, thus acting
properly when a non-top level required property is encountered in a QML
file.

A new test, `qmltc_build_failures`, is added to keep track of the
behavior and ensure that `qmltc` fails at the build-level when this form
of error is encountered.

Task-number: QTBUG-120698
Change-Id: I45f975f1258a42fd2eb66283c1d3611152278fcc
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

tests/auto/cmake/CMakeLists.txt

@@ -155,5 +155,7 @@ if(TARGET Qt::Quick)
             )
         endif()
     endif()
+
+    add_subdirectory(qmltc_build_failures)
 endif()
 

tests/auto/cmake/qmltc_build_failures/CMakeLists.txt

@@ -0,0 +1,7 @@
+# Copyright (C) 2024 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+project(qmltc_build_failures)
+
+_qt_internal_test_expect_build_fail(nontoplevelrequiredproperty)

tests/auto/cmake/qmltc_build_failures/nontoplevelrequiredproperty/CMakeLists.txt

@@ -0,0 +1,26 @@
+# Copyright (C) 2024 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+
+project(nontoplevelrequiredproperty)
+
+find_package(Qt6 REQUIRED Quick REQUIRED ${Qt6Tests_PREFIX_PATH})
+
+qt_standard_project_setup()
+
+qt_add_executable(executable
+     main.cpp
+)
+
+qt6_add_qml_module(executable
+    VERSION 1.0
+    URI QmltcBuildFailures
+    QML_FILES
+        Main.qml
+    DEPENDENCIES
+        QtQuick
+    ENABLE_TYPE_COMPILER
+)
+
+target_link_libraries(executable PRIVATE Qt6::Quick)

tests/auto/cmake/qmltc_build_failures/nontoplevelrequiredproperty/Main.qml

@@ -0,0 +1,10 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+import QtQuick
+
+Item {
+    Item {
+        required property int foo
+    }
+}

tests/auto/cmake/qmltc_build_failures/nontoplevelrequiredproperty/main.cpp

@@ -0,0 +1,3 @@
+#include "main.h"
+
+int main() { }