stream-clone-test: simplify case testing obsolescence
There is only two important things in this test:
- the number of file we send, to show we picked the obsstore.
- the resulting state, to show we did alter things in the process.
The rest are of the number are very fragile and consume a lot of time for little
value when adjusting formats, caches, and protocol.
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}