Why isn't the version file generated in the webapp folder by yarn build

[n-peugnet]

Is your suggestion related to a problem? Please describe.
On my server, I decided to build Riot from sources as this was the easiest way to update it once new versions are released. I have a virtualhost pointing to the webapp folder and I just have to run yarn build to build the latest version. But this doesn't generate the version file as stated in the doc.
It's not that much of a problem as I just have to add it manually afterwards and I imagine that there are reasons why it's made this way, but I am wondering why this step isn't executed by the build target.

Describe the solution you'd like
Ideally I would like to just run yarn build which would generate a version file in the webapp folder the same way the package.sh script does it.