std::reverse_iterator<QDomNodeList::It>::operator-> fails on clang c++17

Failure Summary:
The failure is related to the change that added iterator support to QDomNodeList (QTBUG-115076). The compilation error occurs due to the use of operator-> on a reverse iterator, which is not supported because the addressof function is deleted for rvalue references.

Log snippet:

```
error: call to deleted function 'addressof'
return std::addressof(operator*());
^~~~~~~~~~~~~~
note: in instantiation of member function 'std::reverse_iterator<QDomNodeList::It>::operator->' requested here
QCOMPARE(iter->attributes().item(0).nodeValue().toInt(), i–);

```

Failed Platform:
macos-14-arm64-developer-build

Note: When fixed, remove `#if __cplusplus >= 202002L` from reverse iterator test in tst_qdom.