This is just a recommendation to get results which are reproducable and not let users install dysfunctional developer versions accidentally. It would probably also speed up the installation considerably. There are packages available for all recent ubuntu and fedora versions see https://sumo.dlr.de/docs/Downloads.php#linux. The packages should also take care of setting SUMO_HOME correctly.
The install script still builds SUMO from the head of git as far as I can see. If you do not want to go the package management path, I just wanted to mention that you could also do pip install eclipse-sumo.
This is just a recommendation to get results which are reproducable and not let users install dysfunctional developer versions accidentally. It would probably also speed up the installation considerably. There are packages available for all recent ubuntu and fedora versions see https://sumo.dlr.de/docs/Downloads.php#linux. The packages should also take care of setting SUMO_HOME correctly.