[Insights] Updating ChangeLog.md with the lastest fixes.

Author: gucalder

src/ResourceManager/Insights/Commands.Insights/ChangeLog.md

@@ -19,6 +19,13 @@
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 ## Current Release
 
+* Fixed issues #6833 and #7102 (Diagnostic Settings area)
+    - Issues with the default name, i.e. "service", during creation and listing/getting of diagnostic settings
+    - Issues creating diagnostic settings with categories
+
+* Added deprecation message for metrics time grains parameters
+    - Timegrains parameters are still being accepted (this is a non-breaking change,) but they are ignored in the backend since only PT1M is valid
+
 ## Version 5.1.3
 * Fixed issue with default resource groups not being set.
 * Updated common runtime assemblies