Bump NUnit from 3.14.0 to 4.1.0 (#3)

Bumps [NUnit](https://github.com/nunit/nunit) from 3.14.0 to 4.1.0.
- [Release notes](https://github.com/nunit/nunit/releases)
- [Changelog](https://github.com/nunit/nunit/blob/master/CHANGES.md)
- [Commits](nunit/nunit@v3.14.0...4.1.0)

---
updated-dependencies:
- dependency-name: NUnit
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

LightChain.UnitTests/LightChain.UnitTests.csproj

@@ -17,7 +17,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="NUnit" Version="3.14.0" />
+    <PackageReference Include="NUnit" Version="4.1.0" />
     <PackageReference Include="NUnit.Analyzers" Version="3.9.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
   </ItemGroup>