Add QDateEdit to the fallback property list in qwizard.cpp

[Schachigel]

QDateEdit, derived from QDateTimeEdit, must not use the dateTime property, because it defaults to UTC time zone. The convertion back to localtime (e.g. in the setField / field mechanism of a QWizard / QWizardPage can make the date change, if the time is 00:00 or close to it. As a consequence in

setField( fieldname, QDateTime( aDate, aTime));
auto d =field(fieldname);
the day of d might be different form the day in aDate.

see also qdatetimeedit.cpp line 190 and 1705 (QDateEdit uses UTC) (construction of QDateTimeEdit (using localtime) and QDateTime (using UTC) and
https://forum.qt.io/topic/163954/setfield-or-qdateedit-modify-my-data/6
as a closer analysis

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