Update openai old test

Author: CharlesDuboisSAP

foundation-models/openai/src/main/java/com/sap/ai/sdk/foundationmodels/openai/model/OpenAiChatCompletionDelta.java

@@ -21,6 +21,11 @@ public class OpenAiChatCompletionDelta extends OpenAiCompletionOutput implements
   @Getter(onMethod_ = @Nonnull)
   private List<OpenAiDeltaChatCompletionChoice> choices;
 
+  /** error field in case of an error. */
+  @JsonProperty("error")
+  @Getter(onMethod_ = @Nullable)
+  private Object error;
+
   /**
    * Can be used in conjunction with the seed request parameter to understand when backend changes
    * have been made that might impact determinism.
@@ -62,6 +67,6 @@ && getChoices().get(0).getIndex() == 0) {
 
   @Override
   public boolean isError() {
-    return false;
+    return error != null;
   }
 }

foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiClientGeneratedTest.java

@@ -298,7 +298,7 @@ void streamChatCompletionDeltasErrorHandling() throws IOException {
       try (var stream = client.streamChatCompletionDeltas(request)) {
         assertThatThrownBy(() -> stream.forEach(System.out::println))
             .isInstanceOf(OpenAiClientException.class)
-            .hasMessage("Failed to parse response");
+            .hasMessage("exceeded token rate limit");
       }
 
       Mockito.verify(inputStream, times(1)).close();

foundation-models/openai/src/test/java/com/sap/ai/sdk/foundationmodels/openai/OpenAiClientTest.java

@@ -262,7 +262,7 @@ void streamChatCompletionDeltasErrorHandling() throws IOException {
       try (var stream = client.streamChatCompletionDeltas(request)) {
         assertThatThrownBy(() -> stream.forEach(System.out::println))
             .isInstanceOf(OpenAiClientException.class)
-            .hasMessage("Failed to parse response");
+            .hasMessage("exceeded token rate limit");
       }
 
       Mockito.verify(inputStream, times(1)).close();

foundation-models/openai/src/test/resources/streamChatCompletionError.txt

@@ -1,2 +1,2 @@
 data: {"choices":[],"created":0,"id":"","model":"","object":"","prompt_filter_results":[{"prompt_index":0,"content_filter_results":{"hate":{"filtered":false,"severity":"safe"},"self_harm":{"filtered":false,"severity":"safe"},"sexual":{"filtered":false,"severity":"safe"},"violence":{"filtered":false,"severity":"safe"}}}]}
-{"error":{"code":"429","message":"exceeded token rate limit"}}
+data: {"error":{"code":"429","message":"exceeded token rate limit"}}