fix: add case for error http status (#8)

This should prevent a raised error like such:

```
(CaseClauseError no case clause matching: {:ok, %Finch.Response{body: "", headers: [{"datadog-agent-state", "3e08d91eabb10dd5b61fe89c78d84597c33b237eea8bed02ca3e8193ff1beac8"}, {"datadog-agent-version", "7.41.1"}], status: 502}})
```

Instead, it will catch the error and run `Logger.error("Error sending
metrics to Datadog", error: error)`. While still noisy in logs, it
should not show up in error reporters like Sentry or DataDog.

lib/datadog/data_streams/transport.ex

@@ -34,6 +34,7 @@ defmodule Datadog.DataStreams.Transport do
       {:ok, %Finch.Response{body: %{"error" => error}}} -> {:error, error}
       # This is an odd occurrence, but if the status code shows ok, then alright
       {:ok, %Finch.Response{status: status}} when status in 200..399 -> :ok
+      {:ok, %Finch.Response{} = resp} -> {:error, resp}
       {:error, any} -> {:error, any}
     end
   end