🛠️ Increase max completion tokens from 500 to 800 for improved story generation

Author: roryp

04-PracticalSamples/petstory/src/main/java/com/example/petstory/StoryService.java

@@ -60,7 +60,7 @@ public String generateStory(String description) {
                     .model(modelName)
                     .addSystemMessage(systemPrompt)
                     .addUserMessage(userPrompt)
-                    .maxCompletionTokens(500)
+                    .maxCompletionTokens(800)
                     .temperature(0.8)
                     .build();