Added OPENVINO_GENAI_EXPORTS for generation config property.

Author: popovaan

src/cpp/include/openvino/genai/llm_pipeline.hpp

@@ -270,7 +270,7 @@ class OPENVINO_GENAI_EXPORTS LLMPipeline {
 };
 
 OPENVINO_GENAI_EXPORTS std::pair<std::string, Any> streamer(StreamerVariant func);
-std::pair<std::string, Any> generation_config(const GenerationConfig& config);
+OPENVINO_GENAI_EXPORTS std::pair<std::string, Any> generation_config(const GenerationConfig& config);
 
 }  // namespace genai
 }  // namespace ov