chore: Bump the testing-packages group with 1 update

Bumps NUnit from 4.4.0 to 4.5.0

---
updated-dependencies:
- dependency-name: NUnit
  dependency-version: 4.5.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: testing-packages
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

OpenReferralApi.Tests/OpenReferralApi.Tests.csproj

@@ -13,7 +13,7 @@
         <PackageReference Include="coverlet.collector" Version="8.0.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.1" />
         <PackageReference Include="Moq" Version="4.20.72" />
-        <PackageReference Include="NUnit" Version="4.4.0" />
+        <PackageReference Include="NUnit" Version="4.5.0" />
         <PackageReference Include="NUnit.Analyzers" Version="4.11.2" />
         <PackageReference Include="NUnit3TestAdapter" Version="6.1.0" />
     </ItemGroup>