Bump the test-dependencies group with 1 update (#957)

Bumps Verify.NUnit from 30.11.0 to 30.13.0

---
updated-dependencies:
- dependency-name: Verify.NUnit
  dependency-version: 30.13.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: test-dependencies
...

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

Author: dependabot[bot]

NGitLab.Mock.Tests/NGitLab.Mock.Tests.csproj

@@ -14,6 +14,6 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="NUnit3TestAdapter" Version="5.1.0" />
-    <PackageReference Include="Verify.NUnit" Version="30.11.0" />
+    <PackageReference Include="Verify.NUnit" Version="30.13.0" />
   </ItemGroup>
 </Project>