Update streaming.mdx (#28055)

fix: correct grammar in documentation for streaming modes

Updated sentence to clarify usage of "choose" in "When using the stream
and astream methods with LangGraph, you can choose one or more streaming
modes..." for better readability.

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docs/docs/concepts/streaming.mdx

@@ -77,7 +77,7 @@ When using `stream()` or `astream()` with chat models, the output is streamed as
 
 [LangGraph](/docs/concepts/architecture#langgraph) compiled graphs are [Runnables](/docs/concepts/runnables) and support the standard streaming APIs.
 
-When using the *stream* and *astream* methods with LangGraph, you can **one or more** [streaming mode](https://langchain-ai.github.io/langgraph/reference/types/#langgraph.types.StreamMode) which allow you to control the type of output that is streamed. The available streaming modes are:
+When using the *stream* and *astream* methods with LangGraph, you can choose **one or more** [streaming mode](https://langchain-ai.github.io/langgraph/reference/types/#langgraph.types.StreamMode) which allow you to control the type of output that is streamed. The available streaming modes are:
 
 - **"values"**: Emit all values of the [state](https://langchain-ai.github.io/langgraph/concepts/low_level/) for each step.
 - **"updates"**: Emit only the node name(s) and updates that were returned by the node(s) after each step.