Renovate QString splits with newer enum in Gui

[YakoYakoYokuYoku]

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What does this pull request do?

QString::SplitBehaviour has been deprecated in Qt 5 and Qt::SplitBehaviour is recommended instead.

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Built Natron and used the node graph editor.

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[devernay]

what about

#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
#define QtSkipEmptyParts Qt::SkipEmptyParts
#else
#define QtSkipEmptyParts QString::SkipEmptyParts
#endif

?

[YakoYakoYokuYoku]

I'm not gonna do that due to only a few of the sources uses the SplitBehaviour enum member and that I don't want to use preprocessor defines, so that we can just delete the obsolete portions in one swoop.

[devernay]

ok I'm fine with either solution