Fix Import BedrockChat (#10485)

- Description: Couldn't import BedrockChat from the chat_models
  - Issue: the issue # it fixes (if applicable),
  - Dependencies: N/A
  - Issues: #10468

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Co-authored-by: Ali Soliman <alisaws@amazon.nl>
Co-authored-by: Bagatur <baskaryan@gmail.com>

libs/langchain/langchain/chat_models/__init__.py

@@ -20,6 +20,7 @@ an interface where "chat messages" are the inputs and outputs.
 from langchain.chat_models.anthropic import ChatAnthropic
 from langchain.chat_models.anyscale import ChatAnyscale
 from langchain.chat_models.azure_openai import AzureChatOpenAI
+from langchain.chat_models.bedrock import BedrockChat
 from langchain.chat_models.ernie import ErnieBotChat
 from langchain.chat_models.fake import FakeListChatModel
 from langchain.chat_models.google_palm import ChatGooglePalm
@@ -35,6 +36,7 @@ from langchain.chat_models.vertexai import ChatVertexAI
 
 __all__ = [
     "ChatOpenAI",
+    "BedrockChat",
     "AzureChatOpenAI",
     "FakeListChatModel",
     "PromptLayerChatOpenAI",