Update git submodules

* Update plugins/replication from branch 'master'
  - Removed the recommendation for ssh
    
    As discussed many times during the Gerrit conferences and hackathons,
    Git/SSH replication on Gerrit isn't stable enough due to the JSch
    client stack. Removing the recommendation from the documentation
    may help in choosing alternative methods.
    
    Change-Id: I3c8646135999d6cbb99b58d83d42655d25ea23e9
    
diff --git a/plugins/replication b/plugins/replication
index bb5e2e0..3103cdc 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit bb5e2e02f4a1a932dc985642e7c028d9285ab0cd
+Subproject commit 3103cdc028dfb1d7bc51883981cad67d94e98352