soup-session: fix up the SoupRequest requeuing logic

soup-session: fix up the SoupRequest requeuing logic

Split the "this message is likely to be requeued" logic into a single
function that the sync and async codepaths can share, and fix it to
not think that SOUP_MESSAGE_NO_REDIRECT messages will be redirected,
or that messages that disable SOUP_TYPE_AUTH_MANAGER will be
authenticated.