ceph-object-corpus: update with v0.52 objects

These were generated a few days prior to v0.52 release, but well after
freeze.

Signed-off-by: Sage Weil <sage@inktank.com>

diff --git a/ceph-object-corpus b/ceph-object-corpus
index 4d64c3751101141a34beadf74c3e9f013bce550c..7f23ee1127101d311ec0c50adb719367a0789fad 160000 (submodule)
--- a/ceph-object-corpus
+++ b/ceph-object-corpus
@@ -1 +1 @@
-Subproject commit 4d64c3751101141a34beadf74c3e9f013bce550c
+Subproject commit 7f23ee1127101d311ec0c50adb719367a0789fad