Bump OpenFeature in /openfeature/provider_tests/dotnet-integration-tests

Bumps [OpenFeature](https://github.com/open-feature/dotnet-sdk) from 1.4.1 to 1.5.0.
- [Release notes](https://github.com/open-feature/dotnet-sdk/releases)
- [Changelog](https://github.com/open-feature/dotnet-sdk/blob/main/CHANGELOG.md)
- [Commits](open-feature/dotnet-sdk@v1.4.1...v1.5.0)

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

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

openfeature/provider_tests/dotnet-integration-tests/ProviderTests/ProviderTests.csproj

@@ -16,7 +16,7 @@
         <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
         <PackageReference Include="NUnit.Analyzers" Version="4.1.0" />
         <PackageReference Include="coverlet.collector" Version="6.0.2" />
-        <PackageReference Include="OpenFeature" Version="1.4.1" />
+        <PackageReference Include="OpenFeature" Version="1.5.0" />
         <PackageReference Include="OpenFeature.Contrib.GOFeatureFlag" Version="0.1.5" />
     </ItemGroup>