Fix ruff linting errors - remove unused imports

- Remove unused 'import os' and 'import warnings' from trl/experimental/orpo/orpo_trainer.py
- Remove unused 'from typing import Any' from trl/trainer/orpo_trainer.py

Author: behroozazarkhalili

trl/experimental/orpo/orpo_trainer.py

@@ -13,10 +13,8 @@
 # limitations under the License.
 
 import inspect
-import os
 import random
 import textwrap
-import warnings
 from collections import defaultdict
 from collections.abc import Callable
 from contextlib import nullcontext

trl/trainer/orpo_trainer.py

@@ -14,7 +14,6 @@
 
 import warnings
 from collections.abc import Callable
-from typing import Any
 
 import torch
 import torch.nn as nn