Qt6: use new QSqlField constructor with QMetaType

[Be-ing]

[56/585] Building CXX object CMakeFiles/mixxx-lib.dir/src/dialog/dlgreplacecuecolor.cpp.o
In file included from ../src/dialog/dlgreplacecuecolor.cpp:12:
../src/library/queryutil.h: In constructor ‘FieldEscaper::FieldEscaper(const QSqlDatabase&)’:
../src/library/queryutil.h:77:15: warning: ‘QSqlField::QSqlField(const QString&, QVariant::Type, const QString&)’ is deprecated: Use the constructor using a QMetaType instead [-Wdeprecated-declarations]
   77 |               m_stringField("string", QVariant::String) {
      |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/qt6/QtSql/QtSql:9,
                 from ../src/library/queryutil.h:4,
                 from ../src/dialog/dlgreplacecuecolor.cpp:12:
/usr/include/qt6/QtSql/qsqlfield.h:85:5: note: declared here
   85 |     QSqlField(const QString& fieldName, QVariant::Type type, const QString &tableName = QString())
      |     ^~~~~~~~~

[Be-ing]

Suggested change

	m_stringField("string", QVariant::String){
	m_stringField("string", QVariant::String) {

pre-commit insists on removing the space here... whatever 🤷

[uklotzde]

m_stringField("string",
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
QMetaType(QMetaType::QString)
#else
QVariant::String
#endif
) {

or otherwise try to move only the opening curly brace outside of the #ifdef.

[uklotzde]

m_stringField("string",
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
QMetaType(QMetaType::QString)
#else
QVariant::String
#endif
) {

or otherwise try to move only the opening curly brace outside of the #ifdef.

[uklotzde]

Thank you! LGTM