Update git submodules

* Update plugins/replication from branch 'stable-3.1'
  to 56b7814354c04448da9ba5fddcbe732de02f68c1
  - Merge branch 'stable-3.0' into stable-3.1
    
    * stable-3.0:
      ReplicationFileBasedConfig: fix UnusedException error from ErrorProne
      Clarify that starred-changes ref is not needed on slaves
    
    Move the fix in ReplicationFileBasedConfig to DestinationsCollection.
    
    Change-Id: I2fca1802a26aaf37ba5e6edc81eaa799ac3b27fe
    
  - Merge branch 'stable-2.16' into stable-3.0
    
    * stable-2.16:
      ReplicationFileBasedConfig: fix UnusedException error from ErrorProne
    
    Change-Id: Ia6142dea1802cb44b83a0b1abb657f4e8510fe8c
    
  - ReplicationFileBasedConfig: fix UnusedException error from ErrorProne
    
    Change-Id: I2b04ba8cb9d88e2a40284f0b40195a522ac260e2
    
  - Merge branch 'stable-2.16' into stable-3.0
    
    * stable-2.16:
      Clarify that starred-changes ref is not needed on slaves
    
    Change-Id: Id58a2c1038df9a576312a732ffe2429b7382a5d5
    
  - Clarify that starred-changes ref is not needed on slaves
    
    When using the replication plugin to push to a Gerrit slave
    or to a standard Git repository, refs/starred-changes/* is not
    needed in the replication.config.
    
    Change-Id: Ia77da5a0a8b0247470507bf28680117801c441d3
    
diff --git a/plugins/replication b/plugins/replication
index 0d91ffd..56b7814 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit 0d91ffd189297f511c93d40a864978b5774805c1
+Subproject commit 56b7814354c04448da9ba5fddcbe732de02f68c1