build(deps): bump System.Threading.RateLimiting from 8.0.0 to 9.0.0 (#20

)

Bumps [System.Threading.RateLimiting](https://github.com/dotnet/runtime) from 8.0.0 to 9.0.0.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v8.0.0...v9.0.0)

---
updated-dependencies:
- dependency-name: System.Threading.RateLimiting
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

RateLimitDotNet/RateLimitDotNet.csproj

@@ -11,7 +11,7 @@
     <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.11" />
     <PackageReference Include="Microsoft.AspNetCore.RateLimiting" Version="7.0.0-rc.2.22476.2" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="7.1.0" />
-    <PackageReference Include="System.Threading.RateLimiting" Version="8.0.0" />
+    <PackageReference Include="System.Threading.RateLimiting" Version="9.0.0" />
   </ItemGroup>
 
 </Project>