Add summarization task type for HuggingFace APIs (#4721)

# Add summarization task type for HuggingFace APIs

Add summarization task type for HuggingFace APIs.
This task type is described by [HuggingFace inference
API](https://huggingface.co/docs/api-inference/detailed_parameters#summarization-task)

My project utilizes LangChain to connect multiple LLMs, including
various HuggingFace models that support the summarization task.
Integrating this task type is highly convenient and beneficial.

Fixes #4720

tests/integration_tests/llms/test_self_hosted_llm.py

@@ -43,6 +43,19 @@ def test_self_hosted_huggingface_pipeline_text2text_generation() -> None:
     assert isinstance(output, str)
 
 
+def test_self_hosted_huggingface_pipeline_summarization() -> None:
+    """Test valid call to self-hosted HuggingFace summarization model."""
+    gpu = get_remote_instance()
+    llm = SelfHostedHuggingFaceLLM(
+        model_id="facebook/bart-large-cnn",
+        task="summarization",
+        hardware=gpu,
+        model_reqs=model_reqs,
+    )
+    output = llm("Say foo:")
+    assert isinstance(output, str)
+
+
 def load_pipeline() -> Any:
     """Load pipeline for testing."""
     model_id = "gpt2"