Update changelog for integrations/cohere (#2087)

Co-authored-by: anakin87 <44616784+anakin87@users.noreply.github.com>

Author: HaystackBot

integrations/cohere/CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## [integrations/cohere-v5.2.0] - 2025-07-10
+
+### 🐛 Bug Fixes
+
+- Update Cohere to client 5.16.0 (#2086)
+
+
 ## [integrations/cohere-v5.1.1] - 2025-07-10
 
 ### 🌀 Miscellaneous