Bump MessagePack from 2.5.172 to 2.5.187 (#367)

Bumps [MessagePack](https://github.com/MessagePack-CSharp/MessagePack-CSharp) from 2.5.172 to 2.5.187.
- [Release notes](https://github.com/MessagePack-CSharp/MessagePack-CSharp/releases)
- [Changelog](https://github.com/MessagePack-CSharp/MessagePack-CSharp/blob/master/prepare_release.ps1)
- [Commits](MessagePack-CSharp/MessagePack-CSharp@v2.5.172...v2.5.187)

---
updated-dependencies:
- dependency-name: MessagePack
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

src/Directory.Packages.props

@@ -30,7 +30,7 @@
     </ItemGroup>
     <!--Custom Serialization Examples-->
     <ItemGroup>
-        <PackageVersion Include="MessagePack" Version="2.5.172" />
+        <PackageVersion Include="MessagePack" Version="2.5.187" />
     </ItemGroup>
     <!-- SourceLink support for all Akka.NET projects -->
     <ItemGroup>