docs: cleanup docs so the yields section renders correctly (strands-agents#820)

Author: afarntrog

src/strands/agent/agent.py

@@ -547,12 +547,12 @@ async def stream_async(
 
         Yields:
             An async iterator that yields events. Each event is a dictionary containing
-            information about the current state of processing, such as:
+               information about the current state of processing, such as:
 
-            - data: Text content being generated
-            - complete: Whether this is the final chunk
-            - current_tool_use: Information about tools being executed
-            - And other event data provided by the callback handler
+                - data: Text content being generated
+                - complete: Whether this is the final chunk
+                - current_tool_use: Information about tools being executed
+                - And other event data provided by the callback handler
 
         Raises:
             Exception: Any exceptions from the agent invocation will be propagated to the caller.