Update CHANGELOG-EE.md for 12.4.0-ee

[ci skip]

ee/changelogs/unreleased/34291-code-owner-ribbon.yml

----
-title: Add alert message for feature 'require approval from code owners' being moved
-merge_request: 18715
-author:
-type: changed

ee/changelogs/unreleased/5503-dast-for-the-default-branch.yml

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-title: Implement DAST for default branches
-merge_request: 17789
-author:
-type: added

ee/changelogs/unreleased/5769-add-environment-drop-down-to-pod-logs.yml

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-title: Add environment dropdown to pod logs screen
-merge_request: 17532
-author:
-type: changed

ee/changelogs/unreleased/64481-project-defined-metrics-dashboards-always-show-no-data-found-sta.yml

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-title: Fix project-defined metrics dashboards not rendering
-merge_request: 16589
-author:
-type: fixed

ee/changelogs/unreleased/66293-webide-renaming.yml

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-title: Fixed renaming changed files
-merge_request: 16539
-author:
-type: fixed

ee/changelogs/unreleased/7968-case-insensitive-diff.yml

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-title: Display appropriate approval status icon next to license
-merge_request: 17613
-author:
-type: fixed

ee/changelogs/unreleased/9102-hide-dismissed-vulnerabilities-dismiss-action.yml

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-title: Implement dismissal behaviour when dismissed vulnerabilities are hidden
-merge_request: 16207
-author:
-type: changed

ee/changelogs/unreleased/add-purchase-point-to-group-billing-page.yml

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-title: Show Billing Plan as Cards in profile and groups
-merge_request: 15437
-author:
-type: added

ee/changelogs/unreleased/add-rate-limiting-to-incident-management-create.yml

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-title: Add rack attack settings for prometheus and generic alert endpoint
-merge_request: 17859
-author:
-type: added

ee/changelogs/unreleased/ag-code-hotspots-finder.yml

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-title: Add new table for recording commit counts per file
-merge_request: 17277
-author:
-type: added

ee/changelogs/unreleased/ajk-designs-system-notes.yml

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-title: Create system notes for design events
-merge_request: 14791
-author:
-type: added

ee/changelogs/unreleased/blacklist-license-approval.yml

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-title: Add License-Check approval UI
-merge_request: 16371
-author:
-type: added

ee/changelogs/unreleased/design-list-of-alert-summary.yml

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-title: Change Prometheus Alert details list from bulleted to description list
-merge_request: 18116
-author: Vitali Tatarintev
-type: changed

ee/changelogs/unreleased/docs-code-owners-api.yml

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-title: Docs for protected branch code owner approval API
-merge_request: 17132
-author:
-type: other

ee/changelogs/unreleased/drop-db_load_balancing_index.yml

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-title: Remove db_load_balancing_index gauge metric
-merge_request: 17561
-author:
-type: removed

ee/changelogs/unreleased/eb-browser-performance-vendored-template.yml

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-title: Add vendored template for Browser Performance Testing
-merge_request: 17319
-author:
-type: added

ee/changelogs/unreleased/enable-pa-ff-by-default.yml

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-title: Enable Productivity Analytics feature by default
-merge_request: 18754
-author:
-type: changed

ee/changelogs/unreleased/expose-cycle-analytics-stages-and-events.yml

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-title: Initial endpoint for exposing Cycle Analytics stages for the new frontend
-merge_request: 16240
-author:
-type: added

ee/changelogs/unreleased/fix-issues-designs-sidebar.yml

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-title: Fix page layout for sidebar on designs view
-merge_request: 17579
-author:
-type: fixed

ee/changelogs/unreleased/fix-scrollhandle-in-time-series.yml

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-title: Fixes scroll handle icon in time series
-merge_request: 16354
-author:
-type: fixed