[ Fix ] fixed analyser type issue, edited documentation

Author: anasfik

README.md

@@ -227,7 +227,7 @@ OpenAIChatCompletionModel chatCompletion = await OpenAI.instance.chat.create(
 in addition to calling `OpenAI.instance.chat.create()` which is a `Future` and will resolve only after the whole chat is generated, you can get a `Stream` of results:
 
 ```dart
-  OpenAIStreamChatCompletionModel chatStream = OpenAI.instance.chat.createStream(
+OpenAIStreamChatCompletionModel chatStream = OpenAI.instance.chat.createStream(
     model: "gpt-3.5-turbo",
     messages: [
       OpenAIChatCompletionChoiceMessageModel(
@@ -237,7 +237,7 @@ in addition to calling `OpenAI.instance.chat.create()` which is a `Future` and w
     ],
   );
 
-  chatStream.listen((chatStreamEvent) {
+chatStream.listen((chatStreamEvent) {
 print(chatStreamEvent); // ...
   })
 ```

lib/src/core/models/completion/stream/sub_models/choices.dart

@@ -12,7 +12,7 @@ class OpenAIStreamCompletionModelChoice {
   final int? logprobs;
 
   /// The reason the completion finished.
-  final finishReason;
+  final String finishReason;
 
   @override
   int get hashCode {

pubspec.yaml

@@ -1,6 +1,6 @@
 name: dart_openai
 description: Dart SDK for openAI Apis (GPT-3 & DALL-E), integrate easily the power of OpenAI's state-of-the-art AI models into their Dart applications.
-version: 1.6.1
+version: 1.6.2
 homepage: https://github.com/anasfik/openai
 repository: https://github.com/anasfik/openai
 documentation: https://github.com/anasfik/openai/blob/main/README.md