Update README.md to clarify triggers feature versioning

- Revised the description of the `triggers` parameter in the README to indicate its beta status and specify the SDK version (0.0.3b1) associated with this feature. This enhances clarity for users regarding the current state of the triggers functionality.

Author: NiveditJain

python-sdk/README.md

@@ -352,7 +352,7 @@ async def create_graph():
 - `secrets` (dict[str, str]): Key/value secrets available to all nodes
 - `retry_policy` (RetryPolicyModel | None): Optional retry policy configuration (beta)
 - `store_config` (StoreConfigModel | None): Graph-level store configuration (beta)
-- `triggers` (list[CronTrigger] | None): Optional list of cron triggers for automatic graph execution
+- `triggers` (list[CronTrigger] | None): Optional list of cron triggers for automatic graph execution (beta: SDK version 0.0.3b1)
 - `validation_timeout` (int): Seconds to wait for validation (default: 60)
 - `polling_interval` (int): Polling interval in seconds (default: 1)