community: Fix SparkLLM error (#18015)

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- [x] **PR title**: "package: description"
- Where "package" is whichever of langchain, community, core,
experimental, etc. is being modified. Use "docs: ..." for purely docs
changes, "templates: ..." for template changes, "infra: ..." for CI
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  - Example: "community: add foobar LLM"

- **Description:** fix SparkLLM  error
- **Issue:** the issue # it fixes, if applicable
- **Dependencies:** any dependencies required for this change
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libs/community/langchain_community/llms/__init__.py

@@ -959,5 +959,5 @@ def get_type_to_cls_dict() -> Dict[str, Callable[[], Type[BaseLLM]]]:
         "yandex_gpt": _import_yandex_gpt,
         "yuan2": _import_yuan2,
         "VolcEngineMaasLLM": _import_volcengine_maas,
-        "SparkLLM": _import_sparkllm(),
+        "SparkLLM": _import_sparkllm,
     }