Update CHANGELOG.md for 12.0.0

[ci skip]

changelogs/unreleased/61049-links-activity-stream.yml

----
-title: Use blue for activity stream links; use monospace font for commit sha
-merge_request:
-author:
-type: other

changelogs/unreleased/61072-link-to-user-profile-not-distinguishable-on-latest-commit-widget.yml

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-title: User link styling for commits
-merge_request: 29150
-author:
-type: other

changelogs/unreleased/61144-style-secondary-button-type-to-be-aligned-with-pattern-library.yml

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-title: Bring secondary button styles up to design standard
-merge_request: 27920
-author:
-type: fixed

changelogs/unreleased/61157-reviewer-roulette-shouldn-t-include-the-author-as-a-possibility.yml

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-title: Excludes MR author from Review roulette
-merge_request: 28886
-author: Jacopo Beschi @jacopo-beschi
-type: fixed

changelogs/unreleased/61313-fix-dropdown-searchbar.yml

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-title: Fix loading.. dropdown at search field
-merge_request: 28275
-author: Pavel Chausov
-type: fixed

changelogs/unreleased/61323-snippet-copy-icon-button-is-misaligned.yml

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-title: Resolve Snippet icon button is misaligned
-merge_request: 28522
-author:
-type: other

changelogs/unreleased/61324-non-project-snippet-new-snippet-button-should-be-green-outline.yml

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-title: Give New Snippet button green outline
-merge_request: 28559
-author:
-type: other

changelogs/unreleased/61339-Add-underline-to-attach-a-file.yml

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-title: Add hover and focus to Attach a file
-merge_request: 28682
-author:
-type: fixed

changelogs/unreleased/61393-emoji-button.yml

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-title: Change default color of award emoji button
-merge_request:
-author:
-type: other

changelogs/unreleased/61441.yml

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-title: Allow user to set primary email first when 2FA is required
-merge_request: 28097
-author: Kartikey Tanna
-type: fixed

changelogs/unreleased/61511-add-expand-collapse-to-project-operation-settings.yml

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-title: Add expand/collapse to error tracking settings
-merge_request: 28619
-author:
-type: added

changelogs/unreleased/61565-merge-request-discussion-text-jumps-when-resolved.yml

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-title: Resolve Merge request discussion text jumps when resolved
-merge_request: 28995
-author:
-type: fixed

changelogs/unreleased/61606-support-string-piwik-website-ids.yml

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-title: "Supports Matomo/Piwik string website ID (\"Protect Track ID\" plugin)"
-merge_request: 28214
-author: DUVERGIER Claude
-type: fixed
\ No newline at end of file

changelogs/unreleased/61629-dependency-installation-error-on-fsevents-1-2-4-with-node-js-12.yml

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-title: Update indirect dependency fsevents from 1.2.4 to 1.2.9
-merge_request: 28220
-author: Takuya Noguchi
-type: other

changelogs/unreleased/61639-flaky-spec-issue-boards-labels-creates-project-label-spec-features-boards-sidebar_spec-rb-350.yml

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-title: Fix dropdown position when loading remote data
-merge_request: 28526
-author:
-type: fixed

changelogs/unreleased/61697-add-project-id-to-le-common-name.yml

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-title: Prevent common name collisions when requesting multiple Let's Encrypt certificates concurrently
-merge_request: 28373
-author:
-type: fixed

changelogs/unreleased/61788-predefined-colours-dont-have-descriptive-labels.yml

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-title: Adds a text label to color pickers to improve accessibility.
-merge_request: 28343
-author: Chris Toynbee
-type: changed

changelogs/unreleased/61795-fix-error-when-moving-issues.yml

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-title: Remove unintended error message shown when moving issues
-merge_request: 28317
-author:
-type: fixed

changelogs/unreleased/61821-tooltip-consistency.yml

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-title: Resolve Tooltip Consistency
-merge_request: 28839
-author:
-type: fixed

changelogs/unreleased/61827-prevent-user-popover-icon-shrink.yml

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-title: Prevent icons from shrinking in User popover when contents exceed container
-merge_request: 28696
-author:
-type: fixed