t5500: make hash independent

This test has hard-coded pkt-lines with object IDs.  The pkt-line
lengths necessarily differ between hash algorithms, so generate these
lines with the packetize helper so they're always the right size.  In
addition, we will require an object-format capability for SHA-256, so
pass that capability on to the upload-pack process.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5500-fetch-pack.sh

diff --git a/t/t5500-fetch-pack.sh b/t/t5500-fetch-pack.sh
index 52dd1a6..8fee99e 100755
--- a/t/t5500-fetch-pack.sh
+++ b/t/t5500-fetch-pack.sh
@@ -871,9 +871,10 @@
 
 	GIT_PROTOCOL=version=2 git upload-pack . <<-EOF >/dev/null
 	0012command=fetch
+	$(echo "object-format=$(test_oid algo)" | packetize)
 	00010013deepen-since 1
-	0032want $(git rev-parse other)
-	0032have $(git rev-parse master)
+	$(echo "want $(git rev-parse other)" | packetize)
+	$(echo "have $(git rev-parse master)" | packetize)
 	0000
 	EOF
 	)