chore: Update Amazon Bedrock integration to use new generic callable …

…(de)serializers for their callback handlers (#452)

* serialize the callback

* fix test

* lint

integrations/amazon_bedrock/src/haystack_integrations/components/generators/amazon_bedrock/chat/chat_generator.py

@@ -6,7 +6,7 @@
 import boto3
 from botocore.exceptions import BotoCoreError, ClientError
 from haystack import component, default_from_dict, default_to_dict
-from haystack.components.generators.utils import deserialize_callback_handler
+from haystack.components.generators.utils import deserialize_callback_handler, serialize_callback_handler
 from haystack.dataclasses import ChatMessage, StreamingChunk
 from haystack.utils.auth import Secret, deserialize_secrets_inplace
 
@@ -248,7 +248,7 @@ def to_dict(self) -> Dict[str, Any]:
             model=self.model,
             stop_words=self.stop_words,
             generation_kwargs=self.model_adapter.generation_kwargs,
-            streaming_callback=self.streaming_callback,
+            streaming_callback=serialize_callback_handler(self.streaming_callback),
         )
 
     @classmethod

integrations/amazon_bedrock/tests/test_amazon_chat_bedrock.py

@@ -58,7 +58,7 @@ def test_to_dict(mock_auto_tokenizer, mock_boto3_session, set_env_variables):
             "model": "anthropic.claude-v2",
             "generation_kwargs": {"temperature": 0.7},
             "stop_words": [],
-            "streaming_callback": print_streaming_chunk,
+            "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
         },
     }