Upgrade replication plugin to latest master revision

Adds the following commits:

3cf0561 - PushOne: Improve logging of lock failure
c27817f - PushOne: Log when skipping deletion of ref

Change-Id: Ie95e8453350a301ca45fc3433545ebc941058a84
diff --git a/plugins/replication b/plugins/replication
index 841ed8f..864bc26 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit 841ed8fe0417a8aef985d1dd4bfd368d9a00b355
+Subproject commit 864bc26714111ed8fd4e7b402e7830482b57cde0