[5.2] Set version to 5.2

[Hackwar]

What the title says.

[brianteeman]

I have tested this item ✅ successfully on 7362494

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[Quy]

I have tested this item ✅ successfully on 7362494

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/42970.}

[Quy]

RTC

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