Bump Verify.DiffPlex from 2.2.0 to 2.2.1

Bumps [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex) from 2.2.0 to 2.2.1.
- [Release notes](https://github.com/VerifyTests/Verify.DiffPlex/releases)
- [Commits](https://github.com/VerifyTests/Verify.DiffPlex/commits/2.2.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

src/core/Akka.API.Tests/Akka.API.Tests.csproj

@@ -30,7 +30,7 @@
     <PackageReference Include="xunit.runner.visualstudio" Version="$(XunitVersion)" />
     <PackageReference Include="PublicApiGenerator" Version="9.3.0" />
     <PackageReference Include="Verify.Xunit" Version="19.13.0" />
-    <PackageReference Include="Verify.DiffPlex" Version="2.2.0" />
+    <PackageReference Include="Verify.DiffPlex" Version="2.2.1" />
   </ItemGroup>
 
 </Project>