Fix lint issues: remove unused imports from guardrail classes

- Remove unused LLM import from hallucination_guardrail.py
- Remove unused LLM, Optional, and Task imports from llm_guardrail.py
- Fixes ruff lint errors: F401 imported but unused

Co-Authored-By: João <joao@crewai.com>

src/crewai/tasks/hallucination_guardrail.py

@@ -8,7 +8,6 @@ Classes:
 
 from typing import Any, Optional, Tuple
 
-from crewai.llm import LLM
 from crewai.llms.base_llm import BaseLLM
 from crewai.tasks.task_output import TaskOutput
 from crewai.utilities.logger import Logger

src/crewai/tasks/llm_guardrail.py

@@ -1,11 +1,9 @@
-from typing import Any, Optional, Tuple
+from typing import Any, Tuple
 
 from pydantic import BaseModel, Field
 
 from crewai.agent import Agent, LiteAgentOutput
-from crewai.llm import LLM
 from crewai.llms.base_llm import BaseLLM
-from crewai.task import Task
 from crewai.tasks.task_output import TaskOutput