There’s no API to update Bugzilla product versions. This is weird because projects like Plasma release dozens of bits of software at the same time and we need to update the version numbers in Bugzilla so people can correctly report bugs against them. Even if it was only 1 bit of software we released it would still be nice to automate that rather than click through lots of web pages.
For Plasma I’ve written a wee shell script which uses Curl to load the relevant page to update the version. It takes a list of Bugzilla products (which in KDE land don’t have any direct relation to Git archives or tars we release so this has to be maintained manually) and a cookie which you need to extract out of your web browser.
git clone git://anongit.kde.org/releasemeby