Test the cmake scripttools module only if widgets is available.

Change-Id: Ia124db1328e9d6b87c9b1b6858103f81e1678355
Reviewed-by: Alexander Neundorf <neundorf@kde.org>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>

tests/auto/cmake/CMakeLists.txt

@@ -9,7 +9,16 @@ find_package(Qt5Core REQUIRED)
 
 include("${_Qt5CTestMacros}")
 
+set(qt_module_includes
+    Script QScriptEngine
+)
+
+if (NOT NO_WIDGETS)
+    list(APPEND qt_module_includes
+        ScriptTools QScriptEngineDebugger
+    )
+endif()
+
 test_module_includes(
-  Script QScriptEngine
-  ScriptTools QScriptEngineDebugger
+    ${qt_module_includes}
 )