fix: remove optional arguments with a default

Author: zimeg

slack_sdk/web/async_client.py

@@ -2908,7 +2908,7 @@ async def chat_startStream(
     async def chat_stream(
         self,
         *,
-        buffer_size: Optional[int] = 256,
+        buffer_size: int = 256,
         channel: str,
         thread_ts: str,
         recipient_team_id: Optional[str] = None,

slack_sdk/web/client.py

@@ -2898,7 +2898,7 @@ def chat_startStream(
     def chat_stream(
         self,
         *,
-        buffer_size: Optional[int] = 256,
+        buffer_size: int = 256,
         channel: str,
         thread_ts: str,
         recipient_team_id: Optional[str] = None,

slack_sdk/web/legacy_client.py

@@ -2910,7 +2910,7 @@ def chat_startStream(
     def chat_stream(
         self,
         *,
-        buffer_size: Optional[int] = 256,
+        buffer_size: int = 256,
         channel: str,
         thread_ts: str,
         recipient_team_id: Optional[str] = None,