ceph-object-corpus: update the submodule

ceph-object-corpus submodule

Signed-off-by: Nitzan Mordechai <nmordech@redhat.com>
(cherry picked from commit 882eaa7ceece9043ebc82e7a700b7dca9af8b066)

diff --git a/ceph-object-corpus b/ceph-object-corpus
index 84714379121c19f89a8145fee179d6388bf74c1e..6b15dbab5629b79bc9364054cf1d3ca6c01d9af2 160000 (submodule)
--- a/ceph-object-corpus
+++ b/ceph-object-corpus
@@ -1 +1 @@
-Subproject commit 84714379121c19f89a8145fee179d6388bf74c1e
+Subproject commit 6b15dbab5629b79bc9364054cf1d3ca6c01d9af2