Langchain Bedrock spans now use correct model; inference profile ARN bug fixed

Estimated end-of-life date, accurate to within three months: 05-2027 See the support level definitions for more information.

Bug Fixes

• LLM Observability: Users auto instrumenting Langchain and using Bedrock inference profiles would have their spans' be associated with the inference profile's ARN instead of the underlying LLM model. We now resolve the correct underlying model if users pass base_model_id to their ChatBedrockConverse instantiation. https://github.com/DataDog/dd-trace-py/pull/18151

Full Changelog: https://github.com/DataDog/dd-trace-py/compare/v4.8.5...v4.8.6