merge lazy import blocks (#6358)

haystack/preview/components/generators/hugging_face_local.py

@@ -9,12 +9,8 @@
 
 SUPPORTED_TASKS = ["text-generation", "text2text-generation"]
 
-with LazyImport(
-    message="PyTorch is needed to run this component. Please install it by following the instructions at https://pytorch.org/"
-) as torch_import:
+with LazyImport(message="Run 'pip install transformers[torch]'") as torch_and_transformers_import:
     import torch
-
-with LazyImport(message="Run 'pip install transformers'") as transformers_import:
     from huggingface_hub import model_info
     from transformers import (
         pipeline,
@@ -127,8 +123,7 @@ def __init__(
             For some chat models, the output includes both the new text and the original prompt.
             In these cases, it's important to make sure your prompt has no stop words.
         """
-        transformers_import.check()
-        torch_import.check()
+        torch_and_transformers_import.check()
 
         pipeline_kwargs = pipeline_kwargs or {}
         generation_kwargs = generation_kwargs or {}