community: Add IPEX-LLM BGE embedding support on both Intel CPU and GPU

[Oscilloscope98]

Description: IPEX-LLM is a PyTorch library for running LLM on Intel CPU and GPU (e.g., local PC with iGPU, discrete GPU such as Arc, Flex and Max) with very low latency. This PR adds ipex-llm integrations to langchain for BGE embedding support on both Intel CPU and GPU.
Dependencies: ipex-llm, sentence-transformers
Contribution maintainer: @Oscilloscope98
tests and docs:

• langchain/docs/docs/integrations/text_embedding/ipex_llm_gpu.ipynb
• langchain/docs/docs/integrations/text_embedding/ipex_llm_gpu.ipynb
• langchain/libs/community/tests/integration_tests/embeddings/test_ipex_llm.py