community[minor]: migrate bigdl-llm to ipex-llm (#19518)

- **Description**: `bigdl-llm` library has been renamed to
[`ipex-llm`](https://github.com/intel-analytics/ipex-llm). This PR
migrates the `bigdl-llm` integration to `ipex-llm` .
- **Issue**: N/A. The original PR of `bigdl-llm` is
https://github.com/langchain-ai/langchain/pull/17953
- **Dependencies**: `ipex-llm` library
- **Contribution maintainer**: @shane-huang

Updated doc:   docs/docs/integrations/llms/ipex_llm.ipynb
Updated test:
libs/community/tests/integration_tests/llms/test_ipex_llm.py

libs/community/tests/integration_tests/llms/test_bigdl_llm.py

@@ -1,11 +1,11 @@
-"""Test BigDL LLM"""
+"""Test BigdlLLM"""
 from langchain_core.outputs import LLMResult
 
-from langchain_community.llms.bigdl import BigdlLLM
+from langchain_community.llms.bigdl_llm import BigdlLLM
 
 
 def test_call() -> None:
-    """Test valid call to baichuan."""
+    """Test valid call to bigdl-llm."""
     llm = BigdlLLM.from_model_id(
         model_id="lmsys/vicuna-7b-v1.5",
         model_kwargs={"temperature": 0, "max_length": 16, "trust_remote_code": True},
@@ -15,7 +15,7 @@ def test_call() -> None:
 
 
 def test_generate() -> None:
-    """Test valid call to baichuan."""
+    """Test valid call to bigdl-llm."""
     llm = BigdlLLM.from_model_id(
         model_id="lmsys/vicuna-7b-v1.5",
         model_kwargs={"temperature": 0, "max_length": 16, "trust_remote_code": True},

libs/community/tests/integration_tests/llms/test_ipex_llm.py

@@ -0,0 +1,25 @@
+"""Test IPEX LLM"""
+from langchain_core.outputs import LLMResult
+
+from langchain_community.llms.ipex_llm import IpexLLM
+
+
+def test_call() -> None:
+    """Test valid call to ipex-llm."""
+    llm = IpexLLM.from_model_id(
+        model_id="lmsys/vicuna-7b-v1.5",
+        model_kwargs={"temperature": 0, "max_length": 16, "trust_remote_code": True},
+    )
+    output = llm("Hello!")
+    assert isinstance(output, str)
+
+
+def test_generate() -> None:
+    """Test valid call to ipex-llm."""
+    llm = IpexLLM.from_model_id(
+        model_id="lmsys/vicuna-7b-v1.5",
+        model_kwargs={"temperature": 0, "max_length": 16, "trust_remote_code": True},
+    )
+    output = llm.generate(["Hello!"])
+    assert isinstance(output, LLMResult)
+    assert isinstance(output.generations, list)