t/helper: use correct object hash in partial-clone helper

The `object_info()` function of the partial-clone helper is responsible
for checking the object ID of a repository other than `the_repository`.
We use `parse_oid_hex()` in this function though, which means that we
still depend on `the_repository->hash_algo`.

Fix this by using the object hash of the function-local repository.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: pks-t

t/helper/test-partial-clone.c

@@ -21,7 +21,7 @@ static void object_info(const char *gitdir, const char *oid_hex)
 
 	if (repo_init(&r, gitdir, NULL))
 		die("could not init repo");
-	if (parse_oid_hex(oid_hex, &oid, &p))
+	if (parse_oid_hex_algop(oid_hex, &oid, &p, r.hash_algo))
 		die("could not parse oid");
 	if (oid_object_info_extended(&r, &oid, &oi, 0))
 		die("could not obtain object info");