Update CHANGELOG.md for 12.8.0

[ci skip]

changelogs/unreleased/35428-web-ide-button-missing-from-project-pages.yml

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-title: Enable Web IDE on projects without Merge Requests
-merge_request: 24508
-author:
-type: fixed

changelogs/unreleased/35473-webide-hash-in-branch-name.yml

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-title: 'WebIDE: Support # in branch names'
-merge_request: 24717
-author:
-type: changed

changelogs/unreleased/35546-child-epic-error-messages.yml

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-title: Improve error messages when adding a child epic
-merge_request: 22688
-author:
-type: fixed

changelogs/unreleased/35552-improve-logging-of-sync-services-alt.yml

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-title: 'Geo: Include host when logging'
-merge_request: 22203
-author:
-type: other

changelogs/unreleased/35671-api-repository-commits-with-order.yml

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-title: 'API: Ability to list commits in order (--topo-order)'
-merge_request: 24702
-author:
-type: added

changelogs/unreleased/35792-saml-bypass-2-factor-authentication-function-does-not-work-with-adf.yml

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-title: Support the bypass 2FA function with ADFS SAML
-merge_request: 23615
-author:
-type: fixed

changelogs/unreleased/35896-graphql-error-stack-trace.yml

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-title: Add Sentry error stack trace to GraphQL API
-merge_request: 23750
-author:
-type: added

changelogs/unreleased/35897-grapghql-error-tracking-list-errors.yml

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-title: Add querying of Sentry errors to Graphql
-merge_request: 21802
-author:
-type: added

changelogs/unreleased/35968-add_path_to_edit_custom_metrics.yml

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-title: Adds path to edit custom metrics in dashboard response
-merge_request: 24645
-author:
-type: added

changelogs/unreleased/36422-add-nuget-installation-commands.yml

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-title: Added NuGet package installation instructions to package details page
-merge_request: 24162
-author:
-type: added

changelogs/unreleased/36505-nuget-the-search-service.yml

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-title: Add specialized index to packages_packages database table
-merge_request: 24182
-author:
-type: other

changelogs/unreleased/36675-add-median-line-to-cycle-analytics-duration-chart.yml

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-title: Add cycle analytics duration chart with median line
-merge_request: 23971
-author:
-type: added

changelogs/unreleased/36739-standalone-vulnerability-page.yml

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-title: Creates a standalone vulnerability page
-merge_request: 20734
-author:
-type: other

changelogs/unreleased/36749-explore-projectscontroller-index-latency.yml

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-title: Limit page number on explore/projects
-merge_request: 22876
-author:
-type: performance

changelogs/unreleased/36854-webide-use-gl-alert.yml

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-title: Fix Web IDE alert message look and feel
-merge_request: 23300
-author: Sean Nichols
-type: fixed

changelogs/unreleased/37012-jira-dvcs-error.yml

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-title: Fix JIRA DVCS retrieving repositories
-merge_request: 23180
-author:
-type: fixed

changelogs/unreleased/37174-move-contribution-analytics-chart-to-echarts.yml

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-title: Move contribution analytics chart to echarts
-merge_request: 24272
-author:
-type: other

changelogs/unreleased/37297-monitor-dashboard-dropdown-controls-caret-icon-is-misaligned.yml

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-title: Fix dropdown caret not being positioned correctly
-merge_request: 24273
-author:
-type: fixed

changelogs/unreleased/37335-conan-name-validation-fixes.yml

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-title: Conan packages are validated based on full recipe instead of name/version alone
-merge_request: 24692
-author:
-type: changed

changelogs/unreleased/37722-configurable-ds-advisory-db.yml

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-title: 'Add CI variables to configure bundler-audit advisory database (Dependency Scanning)'
-merge_request: 23717
-author:
-type: added