Specific tests for QJSEngine fail with Qt 6.6.3 while they successfully passed with Qt 6.7.1

Steps to reproduce:

• Prepare Google test environment.
• Run the attached reproducer. If it runs with Qt 6.6.3, the tests fail and it shows log messages as follows:

  ---

  [ RUN ] suite1.case1
  C:/qt_projects/googletest_test/tst_case1.cpp:24: Failure
  Expected equality of these values:
  js_val.toVariant().toString().toStdString()
  Which is: ""
  "item_name"

  ---

The same tests are successfully passed when it runs with Qt 6.7.1, and the customer says it was also successfully passed with Qt 5.15.15.