docs: fix duplication in registry.yaml (#1698)

Author: ykoh42

registry.yaml

@@ -1894,15 +1894,6 @@
     - usage-api
     - cost-api
 
-- title: How to use the Usage API and Cost API to monitor your OpenAI usage
-  path: examples/completions_usage_api.ipynb
-  date: 2025-01-14
-  authors:
-    - MW-OAI
-  tags:
-    - usage-api
-    - cost-api
-
 - title: Build Your Own Code Interpreter - Dynamic Tool Generation and Execution With o3-mini
   path: examples/object_oriented_agentic_approach/Secure_code_interpreter_tool_for_LLM_agents.ipynb
   date: 2025-02-03