CHANGES: Adds info about: #1786

Author: Felipe Zimmerle

CHANGES

@@ -1,6 +1,8 @@
 v3.0.3 - YYYY-MMM-DD (to be released)
 -------------------------------------
 
+ - Fix race condition in UniqueId::uniqueId()
+   [Issue #1786 - @weliu]
  - Fix memory leak in error message for msc_rules_merge C APIs
    [Issue #1765 - @weliu]
  - Return false in SharedFiles::open() when an error happens