Fix typo on Readme

Author: sashirestela

README.md

@@ -32,7 +32,7 @@ Currently we are supporting the `openai.chatCompletionService()` service only.
 [Anyscale](https://www.anyscale.com/endpoints) is suported by Simple-OpenAI. We can use the class `SimpleOpenAIAnyscale`, which extends the class `BaseSimpleOpenAI`, to start using this provider.
 ```java
 var openai = SimpleOpenAIAnyscale.builder()
-    .apiKey(System.getenv("AZURE_OPENAI_API_KEY"))
+    .apiKey(System.getenv("ANYSCALE_API_KEY"))
     //.baseUrl(customUrl)             Optionally you could pass a custom baseUrl
     //.httpClient(customHttpClient)   Optionally you could pass a custom HttpClient
     .build();
@@ -372,4 +372,4 @@ Examples for each OpenAI service have been created in the folder [demo](https://
 ## 📄 License
 Simple-OpenAI is licensed under the MIT License. See the
 [LICENSE](https://github.com/sashirestela/simple-openai/blob/main/LICENSE) file
-for more information.
+for more information.