Update about-ojs.md

correction to release version and date

learning-ojs/en/about-ojs.md

@@ -11,7 +11,7 @@ Open Journal Systems \(OJS\) is an open source solution to managing and publishi
 
 It has been designed to reduce the time and energy devoted to the clerical and managerial tasks associated with editing a journal, while improving the record-keeping and efficiency of editorial processes. It seeks to improve the scholarly and public quality of journal publishing through a number of innovations, including enhancing the reader experience, making journal policies more transparent, and improving indexing.
 
-This guide covers OJS version 3.3, released in February 2021, and features significant enhancements over the previous versions of the software. We hope you find it helpful for your publishing projects.
+This guide covers OJS version 3.4, released in May 2023, and features significant enhancements over the previous versions of the software. We hope you find it helpful for your publishing projects.
 
 ## Background