Update CHANGELOG.md for 13.9.1-ee

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CHANGELOG.md

@@ -2,6 +2,30 @@
 documentation](doc/development/changelog.md) for instructions on adding your own
 entry.
 
+## 13.9.1 (2021-02-23)
+
+### Fixed (6 changes, 1 of them is from the community)
+
+- Send SIGINT instead of SIGQUIT to puma. !54446 (Jörg Behrmann @behrmann)
+- Reset description template names cache key to reload an updated templates structure. !54614
+- Restore missing horizontal scrollbar on issue boards. !54634
+- Fix keep latest artifacts checkbox being always disabled. !54669
+- Fix Metric tab not showing up on operations page. !54736
+- Fix S3 object storage failing when endpoint is not specified. !54868
+
+### Changed (1 change)
+
+- Updates authorization for linting endpoint. !54492
+
+### Performance (1 change)
+
+- Fix N+1 SQL regression in exporting issues to CSV. !54287
+
+### Other (1 change)
+
+- Fix creating the idx_on_issues_where_service_desk_reply_to_is_not_null index before the post migration. !54346
+
+
 ## 13.9.0 (2021-02-22)
 
 ### Security (1 change)

changelogs/unreleased/322198-fix-metrics-tab.yml

----
-title: Fix Metric tab not showing up on operations page
-merge_request: 54736
-author:
-type: fixed

changelogs/unreleased/fix-email-participants-migration-version-number.yml

----
-title: Fix creating the idx_on_issues_where_service_desk_reply_to_is_not_null index
-  before the post migration
-merge_request: 54346
-author:
-type: other

changelogs/unreleased/fix-keep-artifacts-project-setting.yml

----
-title: Fix keep latest artifacts checkbox being always disabled
-merge_request: 54669
-author:
-type: fixed

changelogs/unreleased/lm-fix-authorization-lint.yml

----
-title: Updates authorization for linting endpoint
-merge_request: 54492
-author:
-type: changed

changelogs/unreleased/psi-board-scroll.yml

----
-title: Restore missing horizontal scrollbar on issue boards
-merge_request: 54634
-author:
-type: fixed

changelogs/unreleased/puma_sigint.yml

----
-title: Send SIGINT instead of SIGQUIT to puma
-merge_request: 54446
-author: Jörg Behrmann @behrmann
-type: fixed

changelogs/unreleased/reset_template_cache_key.yml

----
-title: Reset description template names cache key to reload an updated templates structure
-merge_request: 54614
-author:
-type: fixed

changelogs/unreleased/revert-fb45e290.yml

----
-title: Fix S3 object storage failing when endpoint is not specified
-merge_request: 54868
-author:
-type: fixed

changelogs/unreleased/sh-fix-export-csv-service-nplusone.yml

----
-title: Fix N+1 SQL regression in exporting issues to CSV
-merge_request: 54287
-author:
-type: performance