Bump OpenTelemetry.Exporter.OpenTelemetryProtocol in /Backend

Bumps [OpenTelemetry.Exporter.OpenTelemetryProtocol](https://github.com/open-telemetry/opentelemetry-dotnet) from 1.8.1 to 1.9.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-dotnet/releases)
- [Changelog](https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/RELEASENOTES.md)
- [Commits](open-telemetry/opentelemetry-dotnet@core-1.8.1...core-1.9.0)

---
updated-dependencies:
- dependency-name: OpenTelemetry.Exporter.OpenTelemetryProtocol
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Backend/BackendFramework.csproj

@@ -12,7 +12,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="8.0.1" />
     <PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.8.1" />
-    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.8.1" />
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.9.0" />
     <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.8.1" />
     <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.8.1" />
     <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.8.1" />