Bump Testcontainers from 3.8.0 to 3.9.0

Bumps [Testcontainers](https://github.com/testcontainers/testcontainers-dotnet) from 3.8.0 to 3.9.0.
- [Release notes](https://github.com/testcontainers/testcontainers-dotnet/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-dotnet/blob/develop/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-dotnet@3.8.0...3.9.0)

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

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

test/JanusGraph.Net.IntegrationTest/JanusGraph.Net.IntegrationTest.csproj

@@ -6,7 +6,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="8.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="Testcontainers" Version="3.8.0" />
+    <PackageReference Include="Testcontainers" Version="3.9.0" />
     <PackageReference Include="xunit" Version="2.8.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1" />
     <DotNetCliToolReference Include="dotnet-xunit" Version="2.3.1" />