BridgeAuth should add a `published` line to bridge networkstatus documents
While hacking on getting BridgeDB to use Stem's descriptor parsers, I noticed that
@type bridge-network-status 1.0 documents do not have a
published line, like other networkstatus documents. I proposed that a new
@type bridge-network-status 1.1 descriptor type is created, where Bridge Authorities add a
published line to the head of the document.
Related: #12254 (moved)