add versioning or latest commit information to our about page

[NoamGaash]

It seems like we have some problems with our deployments, or with the caching mechanism, and the frontend isn't always up-to-date on production.
It would help to have some endpoint / entry in the about page that will show the current version

Suggested steps (can be done in same PR or seperated PRs):

1. add the commit hash to environment variable or a file in the docker image
2. expose this variable