Update knowledgebase.mdx

Author: danielkalen

fern/knowledgebase.mdx

@@ -48,7 +48,7 @@ Use the ID of the uploaded file to create a Knowledge Base along with the KB con
 1. Provider: [trieve](https://trieve.ai)
 
 ```bash
-curl --location 'http://api.vapi.ai/knowledge-base' \
+curl --location 'https://api.vapi.ai/knowledge-base' \
 --header 'Content-Type: text/plain' \
 --header 'Authorization: Bearer <YOUR_API_KEY>' \
 --data '{