[http] fix cache-control syntax in EtagHTTPCacheManager
use , to separate cache response directive
closes #5307539
# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s repository side views, usually for notification"""