t5537: make hash size independent
This test modifies a pkt-line stream with sed to change a line with
"shallow" to "unshallow". However, this modification is dependent on
the size of the hash in use; with SHA-256, the pkt-line length is
different, leading to the sed command having no effect.
Use test_oid_cache to specify the correct values for each hash so that
the test continues to work.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>