Bump Microsoft.OpenApi from 1.6.4 to 1.6.5 in /src

Bumps [Microsoft.OpenApi](https://github.com/Microsoft/OpenAPI.NET) from 1.6.4 to 1.6.5.
- [Release notes](https://github.com/Microsoft/OpenAPI.NET/releases)
- [Commits](microsoft/OpenAPI.NET@1.6.4...1.6.5)

---
updated-dependencies:
- dependency-name: Microsoft.OpenApi
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

src/AzureIoTHub.Portal.Server/AzureIoTHub.Portal.Server.csproj

@@ -61,7 +61,7 @@
     </PackageReference>
     <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="7.0.7" />
     <PackageReference Include="Microsoft.Graph" Version="5.14.0" />
-    <PackageReference Include="Microsoft.OpenApi" Version="1.6.4" />
+    <PackageReference Include="Microsoft.OpenApi" Version="1.6.5" />
     <PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" Version="1.18.1" />
     <PackageReference Include="Microsoft.Identity.Web" Version="2.12.2" />
     <PackageReference Include="Microsoft.Identity.Web.UI" Version="2.12.2" />