Bump NUnit3TestAdapter from 4.0.0 to 4.2.1

Bumps [NUnit3TestAdapter](https://github.com/nunit/nunit3-vs-adapter) from 4.0.0 to 4.2.1.
- [Release notes](https://github.com/nunit/nunit3-vs-adapter/releases)
- [Commits](nunit/nunit3-vs-adapter@V4.0.0...V4.2.1)

---
updated-dependencies:
- dependency-name: NUnit3TestAdapter
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

Flow.Launcher.Test/Flow.Launcher.Test.csproj

@@ -50,7 +50,7 @@
   <ItemGroup>
     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="nunit" Version="3.13.2" />
-    <PackageReference Include="NUnit3TestAdapter" Version="4.0.0">
+    <PackageReference Include="NUnit3TestAdapter" Version="4.2.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>