stream-clone-test: simplify the case where server disabled it
We have an option to disable it, we don't need to test it with all protocol
variants.
In addition there is little value in looking at the bytes to bytes details of
the reply. Such check is very fragile and consume a lot of time for little
value when adjusting formats, caches, and protocol.
$ hg init
$ echo 123 > a
$ hg add a
$ hg commit -m "first" a
$ mkdir sub
$ echo 321 > sub/b
$ hg add sub/b
$ hg commit -m "second" sub/b
$ cat sub/b
321
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ cat sub/b 2>/dev/null || echo "sub/b not present"
sub/b not present
$ test -d sub || echo "sub not present"
sub not present