Update CHANGELOG for v7.4.15 (#27281)

CHANGELOG/7.4.md

@@ -1,5 +1,56 @@
 # 7.4 Changelog
 
+## [7.4.15]
+
+### General Cmdlet Updates and Fixes
+
+- Delay update notification for one week to ensure all packages become available (#27229)
+- Close pipe client handles after creating the child ssh process (#27139)
+
+### Tests
+
+- Fix the `PSNativeCommandArgumentPassing` test (#27146)
+
+### Build and Packaging Improvements
+
+<details>
+
+<summary>
+
+<p>Update .NET SDK to 8.0.420</p>
+
+</summary>
+
+<ul>
+<li>Fix the container image for vPack, MSIX vPack and Package pipelines (#27018)</li>
+<li>Update branch for release (#27279)</li>
+<li>Fix package pipeline by adding in PDP-Media directory (#27255)</li>
+<li>Pin ready-to-merge.yml reusable workflow to commit SHA (#27247)</li>
+<li>[StepSecurity] ci: Harden GitHub Actions tags (#27244)</li>
+<li>Build, package, and create VPack for the PowerShell-LTS store package within the same <code>msixbundle-vpack</code> pipeline (#27242)</li>
+<li>Change the display name of PowerShell-LTS package to PowerShell LTS (#27232)</li>
+<li>[StepSecurity] ci: Harden GitHub Actions tokens (#27231)</li>
+<li>Redo windows image fix to use latest image (#27230)</li>
+<li>Separate Store Package Creation, Skip Polling for Store Publish, Clean up PDP-Media (#27228)</li>
+<li>Add comment-based help documentation to build.psm1 functions (#27227)</li>
+<li>Fix a preview detection test for the packaging script (#27226)</li>
+<li>Update the PhoneProductId to be the official LTS id used by Store (#27169)</li>
+<li>Select New MSIX Package Name (#27173)</li>
+<li>Publish <code>.msixbundle</code> package as a VPack (#27187)</li>
+<li>Bump <code>github/codeql-action</code> from 4.32.4 to 4.35.1 (#27143) (#27171) (#27175)</li>
+<li><code>release-upload-buildinfo</code>: replace version-comparison channel gating with metadata flags (#27147)</li>
+<li>Create infrastructure to create two msixs and msixbundles for LTS and Stable (#27145)</li>
+<li>Move <code>_GetDependencies</code> MSBuild target from dynamic generation in <code>build.psm1</code> into <code>Microsoft.PowerShell.SDK.csproj</code> (#27144)</li>
+<li>Bump <code>actions/dependency-review-action</code> from 4.8.3 to 4.9.0 (#27142)</li>
+<li>Bump <code>actions/upload-artifact</code> from 6 to 7 (#27141)</li>
+<li>Separate Official and NonOfficial templates for ADO pipelines (#27140)</li>
+<li>Mirror .NET/runtime ICU version range in PowerShell (#27138)</li>
+</ul>
+
+</details>
+
+[7.4.15]: https://github.com/PowerShell/PowerShell/compare/v7.4.14...v7.4.15
+
 ## [7.4.14]
 
 ### General Cmdlet Updates and Fixes