Fix index out of range error when there are no previous versions of an object

[dpoarch]

Fix index out of range error when there are no previous versions of an object

Traceback (most recent call last):
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/core/handlers/base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/contrib/admin/options.py", line 616, in wrapper
    return self.admin_site.admin_view(view)(*args, **kwargs)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/utils/decorators.py", line 130, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/views/decorators/cache.py", line 44, in _wrapped_view_func
    response = view_func(request, *args, **kwargs)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django/contrib/admin/sites.py", line 232, in inner
    return view(request, *args, **kwargs)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django_handleref/admin.py", line 207, in history_view
    history = self.history(listing.result_list)
  File "/srv/www.peeringdb.com/venv/lib/python3.9/site-packages/django_handleref/admin.py", line 176, in history
    previous = self.version_cls(versions[0]).previous

Exception Type: IndexError at /cp/peeringdb_server/facility/11737/history/
Exception Value: list index out of range