Moving always retrying handler to the tests

Author: jonathan-buttner

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/external/http/retry/AlwaysRetryingResponseHandler.java renamed to x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/external/http/retry/AlwaysRetryingResponseHandler.java

@@ -20,7 +20,6 @@
 import static org.elasticsearch.xpack.inference.external.http.HttpUtils.checkForEmptyBody;
 import static org.elasticsearch.xpack.inference.external.http.HttpUtils.checkForFailureStatusCode;
 
-// TODO remove this
 /**
  * Provides a {@link ResponseHandler} which flags all errors as retryable.
  */