Refactor Task Class Guardrail Type Annotation

- Updated the type annotation for the `guardrails` field in the Task class from `list` to `Sequence` to enhance type safety and compatibility with various sequence types.
- This change improves type checking and aligns with best practices for handling callable functions and string descriptions in guardrail validation.

This update contributes to the overall robustness and maintainability of the Task class.

src/crewai/task.py

@@ -5,7 +5,7 @@ import logging
 import threading
 import uuid
 import warnings
-from collections.abc import Callable
+from collections.abc import Callable, Sequence
 from concurrent.futures import Future
 from copy import copy as shallow_copy
 from hashlib import md5
@@ -153,7 +153,7 @@ class Task(BaseModel):
         description="Function or string description of a guardrail to validate task output before proceeding to next task",
     )
     guardrails: (
-        list[Callable[[TaskOutput], tuple[bool, Any]] | str]
+        Sequence[Callable[[TaskOutput], tuple[bool, Any]] | str]
         | Callable[[TaskOutput], tuple[bool, Any]]
         | str
         | None