fix(test): drop the duplicate embedding_executor arg in the Bedrock KB fake handler

Two branches independently added embedding_executor to the same fake
search handler in this file, #39472 in the middle of the signature and
#39474 at the end. Neither conflicted with the other, so both edits
merged and the function ended up declaring the parameter twice.

Python rejects that at compile time, so the whole module fails to
import and every test in the file is uncollectable, taking the
logging_testing job down on staging.

Keep the earlier of the two, which sits where the real handler declares
the parameter.

tests/logging_callback_tests/test_bedrock_knowledgebase_hook.py

@@ -376,7 +376,6 @@ async def test_bedrock_kb_request_body_has_transformed_filters(
         timeout=None,
         client=None,
         _is_async=False,
-        embedding_executor=None,
     ):
         litellm_params_dict = (
             litellm_params.model_dump(exclude_none=False)