Update CHANGELOG-EE for 8.9.2, 8.8.6, and 8.7.8

[ci skip]

CHANGELOG-EE

@@ -6,6 +6,9 @@ v 8.9.3 (unreleased)
   - Fix encrypted data backwards compatibility after upgrading attr_encrypted gem
   - Fix creating MRs on forks of deleted projects
 
+v 8.9.2
+  - [Elastic] Fix visibility of snippets when searching.
+
 v 8.9.1
   - Improve Geo documentation. !431
   - Fix remote mirror stuck on started issue. !491
@@ -32,6 +35,9 @@ v 8.9.0
   - Ability to lock file or folder in the repository
   - Fix: Git hooks don't fire when committing from the UI
 
+v 8.8.6
+  - [Elastic] Fix visibility of snippets when searching.
+
 v 8.8.5
   - Make sure OAuth routes that we generate for Geo matches with the ones in Rails routes !444
 
@@ -72,6 +78,9 @@ v 8.8.0
   - API requests to /internal/authorized_keys are now tagged properly
   - Geo: Single Sign Out support !380
 
+v 8.7.8
+  - [Elastic] Fix visibility of snippets when searching.
+
 v 8.7.7
   - No EE-specific changes