Add UDL operators for QString/QByteArray to Qt::Literals::QStringLiterals namespace

In scope of QTBUG-98434 _L1 literal operator for QLatin1String has been added to a new Qt::Literals::StringLiterals inline namespace, to avoid conflicts with UDL operators in the global namespace. But now we have inconsistency: other string literal operators (_qs and qba for QString and QByteArray) are in the inline QtLiterals namespace. To avoid inconsistency, add UDL operators _s and _ba for QString and QByteArray to Qt::Literals::StringLiterals, and deprecate the ones from QtLiterals namespace.