Hostname is too long for the field 'name' of 'django.site' table

[psclcnrd]

During the first execution in an empty database, the django.site.name field is too small (50 chars) to accept a long hostname (62 chars in my case). I propose to add the 'SITENAME' variable into .env, and use it into task.py, function '_prepare_site_fixture', into a PR.

[giohappy]

hi @psclcnrd, please read below:

• _prepare_site_fixture is defined both in GeoNode core tasks.py and the GeoNode Project tasks.py. Unfortunately, we still have this duplication, which could be fixed by importing the GeoNode core tasks module inside a GeoNode Project. The few differences between the two modules can be fixed.
• For the reason above I suggest taking the opportunity of your request to unify the tasks.py modules and apply your improvement directly to the GeoNode core.
• This repo is only for internal usage. Issues should be opened on the public repos. In this case I suggest to open on the public GeoNode Project repo. Further issues will be opened to address the duplication.