Update CHANGELOG-EE.md for 12.5.3-ee

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CHANGELOG-EE.md

 Please view this file on the master branch, on stable branches it's out of date.
 
+## 12.5.3
+
+### Performance (1 change)
+
+- Geo - Improve query performance to determine job artifacts to sync when selective sync is enabled. !19583
+
+### Other (1 change)
+
+- Geo - Does not schedule duplicated jobs while backfilling uploads, LFS objects and job artifacts. !20324
+
+
 ## 12.5.1
 
 ### Security (6 changes)

ee/changelogs/unreleased/10286-geo-sql-statement-times-out-whilst-determining-job-artifacts-to-.yml

----
-title: Geo - Improve query performance to determine job artifacts to sync when selective
-  sync is enabled
-merge_request: 19583
-author:
-type: performance

ee/changelogs/unreleased/da-files-does-not-schedule-duplicated-jobs.yml

----
-title: Geo - Does not schedule duplicated jobs while backfilling uploads, LFS objects
-  and job artifacts
-merge_request: 20324
-author:
-type: other