community: fix DallE hidden open_api_key (#26996)

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- [ X] 
    - **Issue:** issue #26941


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Co-authored-by: Erick Friis <erick@langchain.dev>

libs/community/langchain_community/utilities/dalle_image_generator.py

@@ -116,7 +116,9 @@ class DallEAPIWrapper(BaseModel):
 
         if is_openai_v1():
             client_params = {
-                "api_key": self.openai_api_key,
+                "api_key": self.openai_api_key.get_secret_value()
+                if self.openai_api_key
+                else None,
                 "organization": self.openai_organization,
                 "base_url": self.openai_api_base,
                 "timeout": self.request_timeout,