Update git submodules

* Update ChronoSync from branch 'master'
  - docs: mention the contributing guide
    
    Change-Id: Ifa3ad3ee9bea49bb140a5ffa7fdc59a816cf81fe
    refs: #4416
    
diff --git a/ChronoSync b/ChronoSync
index 4e010bc..dc88507 160000
--- a/ChronoSync
+++ b/ChronoSync
@@ -1 +1 @@
-Subproject commit 4e010bced3475517bcd2bc48d08743a5afe4f82d
+Subproject commit dc88507735be66b65aa4dad872fb34af61b552b2