Improve internationalization in KGantt
QDate::toString()
does not fully localize dates: it does not reorder
date components or choose the proper form of month names. For example,
in a Polish locale it returns "maj 1" instead of "1 maja".
Furthermore, in Qt6 date and time toString()
methods will not perform
localization.
This patch switches to QLocale()::toString()
.
BUG: 453292