Update git submodules

* Update plugins/replication from branch 'master'
  to 9ae20871646a0757979e3bef03aaf4e74af8ff73
  - Merge branch 'stable-3.1'
    
    * stable-3.1:
      Make persistent task keys stable
    
    Change-Id: Ib61c40b85aed499781ad3867896a45a08035dfef
    
  - Merge branch 'stable-3.0' into stable-3.1
    
    * stable-3.0:
      Make persistent task keys stable
    
    Change-Id: I2cf44bc4e9810c83fa7afee4290fca25dc50724b
    
  - Merge branch 'stable-2.16' into stable-3.0
    
    * stable-2.16:
      Make persistent task keys stable
    
    Change-Id: Iefda465c739f4669b5394d3c57f7abe0d7513b5f
    
  - Make persistent task keys stable
    
    GSON was used to create json as the input for sha1 task keys, however
    gson can order the json keys differently anytime. Use the values in a
    specific order to create stable keys.
    
    Bug: Issue 11760
    Change-Id: I6900b5ddb3ba8ab7b5cf7803ae9dd551b5980a59
    
diff --git a/plugins/replication b/plugins/replication
index 88eeb9a..9ae2087 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit 88eeb9aa1f15fcf0d891a901990efd5574fa8cf3
+Subproject commit 9ae20871646a0757979e3bef03aaf4e74af8ff73