chore(csharp): Bump System.Diagnostics.DiagnosticSource from 9.0.6 to 9.0.12

---
updated-dependencies:
- dependency-name: System.Diagnostics.DiagnosticSource
  dependency-version: 9.0.12
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

csharp/Directory.Packages.props

@@ -43,7 +43,7 @@
     <PackageVersion Include="OpenTelemetry" Version="1.12.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.Console" Version="1.12.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.12.0" />
-    <PackageVersion Include="System.Diagnostics.DiagnosticSource" Version="9.0.6" />
+    <PackageVersion Include="System.Diagnostics.DiagnosticSource" Version="9.0.12" />
     <PackageVersion Include="System.Net.Http" Version="4.3.4" />
     <PackageVersion Include="System.Net.Http.WinHttpHandler" Version="8.0.2" />
     <PackageVersion Include="System.Text.Json" Version="9.0.9" />