ensure 3XX responses without location header do not throw

[baywet]

follow up to microsoft/kiota#4367
and microsoft/kiota#4190

Implement a unit test with a 304 response, no location header, check the request adapter returns null and doesn't throw.
Most likely this line will need to be adapted.
https://github.com/microsoft/kiota-http-dotnet/blob/d960c5fa7f0661ea294b6962be105890a27fe999/src/HttpClientRequestAdapter.cs#L385

[andrueastman]

Transferring issue as part of #238