Update CHANGELOG-EE.md for 13.9.0-ee

[ci skip]

ee/changelogs/unreleased/300133-update-policy-helper.yml

----
-title: Abstract out details of policy_helper
-merge_request: 52714
-author:
-type: other

ee/changelogs/unreleased/300272-on-swimlanes-board-assignees-search-debounce-is-not-working.yml

----
-title: Fix search debounce for Swimlanes board assignees
-merge_request: 52786
-author:
-type: fixed

ee/changelogs/unreleased/300291-fj-forbid-to-group-wikis-when-read-only.yml

----
-title: Forbid git pushes to group wikis when repo is read only
-merge_request: 52801
-author:
-type: added

ee/changelogs/unreleased/300303-fj-enable-group-wiki-import-export.yml

----
-title: Add group wikis import/export functionality
-merge_request: 53247
-author:
-type: added

ee/changelogs/unreleased/300546-dynamic-plan-renaming.yml

----
-title: Dynamically rename plan title after EoA rollout date
-merge_request: 53473
-author:
-type: added

ee/changelogs/unreleased/301146-1s-server-side-timeouts-on-elasticsearch-counts.yml

----
-title: Set 1s server side timeout on Elasticsearch counts
-merge_request: 53435
-author:
-type: performance

ee/changelogs/unreleased/301146-log-timeouts-from-elasticsearch.yml

----
-title: Track elasticsearch_timed_out_count for all ES requests in log
-merge_request: 54180
-author:
-type: changed

ee/changelogs/unreleased/320885-show-loading-for-vulnerability-list.yml

----
-title: Show loading state for vulnerability list when filter/sort is changed
-merge_request: 53934
-author:
-type: changed

ee/changelogs/unreleased/321380-compliance-framework-assignment-regression.yml

----
-title: Fix issue where maintainers could not set compliance framework for projects
-merge_request: 54071
-author:
-type: fixed

ee/changelogs/unreleased/321620-fix-project-count-only-queries.yml

----
-title: 'Advanced Search: fix project count_only queries'
-merge_request: 54303
-author:
-type: fixed

ee/changelogs/unreleased/Lint-DeprecatedOpenSSLConstant-ee.yml

----
-title: Replace OpenSSL constants with strings
-merge_request: 52431
-author: Takuya Noguchi
-type: other

ee/changelogs/unreleased/aalakkad-use-plan-name-instead-of-code.yml

----
-title: Use plan name instead of plan code in new subscription app
-merge_request: 52414
-author:
-type: other

ee/changelogs/unreleased/add-url-navigation-pipeline-charts-tabs.yml

----
-title: Add URL Navigation to Pipeline Analytics Charts
-merge_request: 52338
-author:
-type: added

ee/changelogs/unreleased/add-user-secure-scan-pings.yml

----
-title: Add usage ping for user secure scans
-merge_request: 49444
-author:
-type: added

ee/changelogs/unreleased/add_project_id_as_cnp_labels.yml

----
-title: Add alert related labels to CiliumNetworkPolicies. The label will contain the
-  project id and will be applicable to both new and existing policies
-merge_request: 53401
-author:
-type: changed

ee/changelogs/unreleased/add_specific_domain_for_alerts_in_graphql.yml

----
-title: Add specific domain for threat management related alerts in order to tie the
-  frontend and backend together.
-merge_request: 51029
-author:
-type: changed

ee/changelogs/unreleased/ag-fix-db-read-only-check.yml

----
-title: Default maintenance_mode value to false if not explicitly set
-merge_request: 54428
-author:
-type: fixed

ee/changelogs/unreleased/ag-remove-maintenance-mode-ff-yml.yml

----
-title: Release maintenance mode
-merge_request: 53895
-author:
-type: added

ee/changelogs/unreleased/ah-kg-add-waiting-period-25Dec.yml

----
-title: Make the waiting period for deletion dynamic on project removal page
-merge_request: 50597
-author:
-type: changed

ee/changelogs/unreleased/axil-okr-advanced-settings-ui.yml

----
-title: Update project's advanced settings UI text
-merge_request: 51442
-author:
-type: other