I have learned that in projects that use version 0.23.x of the docker image, the git extension is not working correctly (see Git Plugin not showing up after upgrade to renkulab-py:3.10-0.23.0).
I cannot check which image version your project uses, since it seems to be private and I do not have access to it, but I can tell you what you need to change in the Dockerfile to get the git extension re-activated.
The Dockerfile should, in the first several lines of the file, have a statement similar to the following:
FROM renku/renkulab-py:3.10-0.23.0 as builder
If you replace 0.23.0 with 0.24.0 in that line of the Dockerfile, commit and push your changes, RenkuLab will rebuild the image. After the image re-build has completed, sessions that you launch should have a working git extension again.
Alternatively, if your project uses a standard template, you should be able to click the Update button on the Settings page, which will automatically make the changes described above.
