[webconfig] fallback to default configs if https ones are not defined
When cubicweb serves a request with an https scheme, it tries to access
``https_uiprops`` and ``https_datadir_urls``. However if those are not defined we
should fallback to unsecure url instead of crashing with a traceback.
There are very valid usecases for undefined https url. For example if your
``base_url``, ``datadir_url`` and uiprops content are already https urls.
Closes #2786643
from cubicweb.schemas.base import in_group, CWSourceSchemaConfig
# copy __permissions__ to avoid modifying a shared dictionary
in_group.__permissions__ = in_group.__permissions__.copy()
in_group.__permissions__['read'] = ('managers',)
cw_for_source = CWSourceSchemaConfig.get_relation('cw_for_source')
cw_for_source.__permissions__ = {'read': ('managers', 'users'),
'add': ('managers',),
'delete': ('managers',)}