Fixed inaccurate import in integrations:providers:bedrock documentation (#8915)

Description:
Fixed inaccurate import in integrations:providers:bedrock documentation

In the current version of the bedrock documentation, page
https://python.langchain.com/docs/integrations/providers/bedrock it
states that the import is from langchain import Bedrock

This has been changed to from langchain.llms.bedrock import Bedrock as
stated in https://python.langchain.com/docs/integrations/llms/bedrock

Issue:
Not applicable

Dependencies
No dependencies required

Tag maintainer
@baskaryan

Twitter handle:
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docs/extras/integrations/providers/bedrock.mdx

@@ -13,7 +13,7 @@ pip install boto3
 See a [usage example](/docs/integrations/llms/bedrock).
 
 ```python
-from langchain import Bedrock
+from langchain.llms.bedrock import Bedrock
 ```
 
 ## Text Embedding Models